Merge remote-tracking branch 'origin/dev' into socket-lwip-raw-udp

Co-authored-by: pre-commit-ci-lite[bot] <117423508+pre-commit-ci-lite[bot]@users.noreply.github.com>

.github/workflows/ci.yml

@@ -244,11 +244,20 @@ jobs:
     steps:
       - name: Check out code from GitHub
         uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+      - name: Read prek version from requirements_test.txt
+        id: prek
+        # requirements_test.txt is the only place the version is pinned, so a
+        # Dependabot bump there is picked up here without a second edit.
+        run: |
+          if ! version=$(sed -nE 's/^prek==([^[:space:]#]+).*/\1/p' requirements_test.txt) || [ -z "$version" ]; then
+            echo "::error::No prek== pin found in requirements_test.txt."
+            exit 1
+          fi
+          echo "version=$version" >> "$GITHUB_OUTPUT"
       - name: Run prek
         uses: j178/prek-action@4e14d07f9231acabce116ccfca13b13dd9755ece # v3.0.0
         with:
-          # Keep in sync with requirements_test.txt.
-          prek-version: "0.4.11"
+          prek-version: ${{ steps.prek.outputs.version }}
           # This job only runs on pull requests, so nothing ever populates
           # the cache on dev. Every run would miss and then write a per-pull
           # request copy, which is what the old seed-cache job existed to

.github/workflows/sync-dependency-versions.yml

@@ -0,0 +1,94 @@
+# Keeps pre-commit hook revs in sync with the requirements files.
+#
+# Dependabot only bumps the pins in requirements*.txt. Some of those tools
+# are pinned again as hook revs in .pre-commit-config.yaml. This workflow
+# runs script/sync_dependency_versions.py against the pull request branch
+# and pushes a commit with the revs updated.
+
+name: Sync dependency versions
+
+on:
+  # pull_request_target rather than pull_request so the App secret is
+  # available on Dependabot pull requests (pull_request runs opened by
+  # Dependabot only see Dependabot secrets). The job below only touches
+  # branches in this repository and only ever executes the script from the
+  # base branch checkout, so fork code never runs with the token.
+  pull_request_target:
+    types: [opened, synchronize, reopened]
+    paths:
+      - requirements_dev.txt
+      - requirements_test.txt
+      - .pre-commit-config.yaml
+      - script/sync_dependency_versions.py
+
+# The push to the pull request branch uses the App token minted below, so
+# the workflow's GITHUB_TOKEN does not need any scopes.
+permissions: {}
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number }}
+  cancel-in-progress: true
+
+jobs:
+  sync:
+    name: Sync pinned versions
+    runs-on: ubuntu-latest
+    # Same-repository branches only: a push to a fork is not possible with
+    # this token, and it keeps untrusted heads out of a privileged job.
+    if: >-
+      github.repository == 'esphome/esphome'
+      && github.event.pull_request.head.repo.full_name == github.repository
+    steps:
+      - name: Generate a token
+        id: generate-token
+        uses: actions/create-github-app-token@bcd2ba49218906704ab6c1aa796996da409d3eb1 # v3.2.0
+        with:
+          client-id: ${{ vars.ESPHOME_GITHUB_APP_CLIENT_ID }}
+          private-key: ${{ secrets.ESPHOME_GITHUB_APP_PRIVATE_KEY }}
+          # A push made with the workflow's own GITHUB_TOKEN would not start
+          # CI on the new commit; a push with the App token does.
+          permission-contents: write  # git push of the sync commit to the pull request branch
+
+      - name: Check out base branch
+        # Provides the script that runs below. Deliberately the base branch
+        # so the pull request cannot change what executes here.
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          ref: ${{ github.event.pull_request.base.sha }}
+          persist-credentials: false
+
+      - name: Check out pull request branch
+        # No allow-unsafe-pr-checkout here on purpose: checkout v7 only
+        # refuses heads that live in a different repository, and the job
+        # condition above already limits runs to same-repository branches.
+        # Leaving it off keeps that refusal as a backstop for fork heads.
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          ref: ${{ github.event.pull_request.head.ref }}
+          path: pull-request
+          token: ${{ steps.generate-token.outputs.token }}
+
+      - name: Set up Python
+        uses: actions/setup-python@5fda3b95a4ea91299a34e894583c3862153e4b97 # v7.0.0
+        with:
+          python-version: "3.12"
+
+      - name: Install yamlrocks
+        # The script edits YAML through yamlrocks. Take the pin from the
+        # base branch requirements so this workflow has no copy of its own.
+        run: pip install "$(grep -E '^yamlrocks==' requirements_test.txt | cut -d'#' -f1)"
+
+      - name: Sync pinned versions
+        run: python script/sync_dependency_versions.py --root pull-request
+
+      - name: Push changes
+        working-directory: pull-request
+        run: |
+          if git diff --quiet; then
+            echo "All pinned versions already match the requirements files."
+            exit 0
+          fi
+          git config user.name "esphome[bot]"
+          git config user.email "115708604+esphome[bot]@users.noreply.github.com"
+          git commit -am "Sync pinned tool versions with requirements files"
+          git push

.pre-commit-config.yaml

@@ -1,7 +1,6 @@
 ---
 # See https://pre-commit.com for more information
 # See https://pre-commit.com/hooks.html for more hooks
-
 ci:
   autoupdate_commit_msg: 'pre-commit: autoupdate'
   autoupdate_schedule: off  # Disabled until ruff versions are synced between deps and pre-commit
@@ -11,7 +10,7 @@ ci:
 repos:
   - repo: https://github.com/astral-sh/ruff-pre-commit
     # Ruff version.
-    rev: v0.16.3
+    rev: v0.16.6
     hooks:
       # Run the linter.
       - id: ruff
@@ -42,7 +41,7 @@ repos:
       - id: pyupgrade
         args: [--py312-plus]
   - repo: https://github.com/adrienverge/yamllint.git
-    rev: v1.37.1
+    rev: v1.38.0
     hooks:
       - id: yamllint
         exclude: ^(\.clang-format|\.clang-tidy)$

AGENTS.md

@@ -553,6 +553,7 @@ file does, and it is the authority when they disagree. The most useful starting
     4.  **Lint:** Run `prek` to ensure code is compliant.
     5.  **Commit:** Commit your changes. There is no strict format for commit messages.
     6.  **Pull Request:** Submit a PR against the `dev` branch. The Pull Request title must start with a `[tag]` prefix. For component work, use the component name (e.g., `[display] Fix bug`, `[abc123] Add new component`); for changes to shared/core code that isn't tied to a single component, use `[core]` (e.g., `[core] Add validator`). Update documentation, examples, and add `CODEOWNERS` entries as needed. Pull requests should always be made using the `.github/PULL_REQUEST_TEMPLATE.md` template - fill out all sections completely without removing any parts of the template.
+    7.  **Comments:** When commenting on GitHub PRs or issues, don't tag contributors, especially bots. Avoid referring to list items (e.g. from reviews) with the form #nn - this will be interpreted by GitHub as a reference to issue or PR nn. Keep comments short and exclude irrelevant details, backstories, restatement of previous comments and anything that is already obvious to the reader.
 
 *   **Documentation Contributions:**
     *   Documentation is hosted in the separate `esphome/esphome.io` repository.
@@ -839,7 +840,7 @@ file does, and it is the authority when they disagree. The most useful starting
         cv.rename_key(
             CONF_OLD_KEY, CONF_NEW_KEY, removed_in="2026.6.0", component="my_component"
         ),
-        cv.Schema({ ... }),
+        cv.Schema({...}),
     )
     ```
     For other deprecations, warn manually during validation:

Doxyfile

@@ -48,7 +48,7 @@ PROJECT_NAME           = ESPHome
 # could be handy for archiving the generated documentation or if some version
 # control system is used.
 
-PROJECT_NUMBER         = 2026.9.0b3
+PROJECT_NUMBER         = 2026.10.0-dev
 
 # Using the PROJECT_BRIEF tag one can provide an optional one line description
 # for a project that appears at the top of each page and should give viewer a

esphome/api_client.py

@@ -23,9 +23,7 @@ from esphome.util import safe_print
 if TYPE_CHECKING:
     from collections.abc import Callable
 
-    from aioesphomeapi.api_pb2 import (
-        SubscribeLogsResponse,  # pylint: disable=no-name-in-module
-    )
+    from aioesphomeapi.api_pb2 import SubscribeLogsResponse  # pylint: disable=no-name-in-module
 
 
 _LOGGER = logging.getLogger(__name__)

esphome/components/audio/audio_reader.cpp

@@ -58,9 +58,6 @@ esp_err_t AudioReader::add_sink(const std::weak_ptr<ring_buffer::RingBuffer> &ou
   if (current_audio_file_ != nullptr) {
     // A transfer buffer isn't ncessary for a local file
     this->file_ring_buffer_ = output_ring_buffer.lock();
-    if (this->file_ring_buffer_ == nullptr) {
-      return ESP_ERR_INVALID_STATE;
-    }
     return ESP_OK;
   }
 

esphome/components/audio/audio_transfer_buffer.cpp

@@ -51,14 +51,14 @@ void AudioTransferBuffer::increase_buffer_length(size_t bytes) { this->buffer_le
 
 void AudioTransferBuffer::clear_buffered_data() {
   this->buffer_length_ = 0;
-  if (this->ring_buffer_ != nullptr) {
+  if (this->ring_buffer_.use_count() > 0) {
     this->ring_buffer_->reset();
   }
 }
 
 void AudioSinkTransferBuffer::clear_buffered_data() {
   this->buffer_length_ = 0;
-  if (this->ring_buffer_ != nullptr) {
+  if (this->ring_buffer_.use_count() > 0) {
     this->ring_buffer_->reset();
   }
 #ifdef USE_SPEAKER
@@ -69,7 +69,7 @@ void AudioSinkTransferBuffer::clear_buffered_data() {
 }
 
 bool AudioTransferBuffer::has_buffered_data() const {
-  if (this->ring_buffer_ != nullptr) {
+  if (this->ring_buffer_.use_count() > 0) {
     return ((this->ring_buffer_->available() > 0) || (this->available() > 0));
   }
   return (this->available() > 0);
@@ -144,7 +144,7 @@ size_t AudioSourceTransferBuffer::transfer_data_from_source(TickType_t ticks_to_
   size_t bytes_to_read = AudioTransferBuffer::free();
   size_t bytes_read = 0;
   if (bytes_to_read > 0) {
-    if (this->ring_buffer_ != nullptr) {
+    if (this->ring_buffer_.use_count() > 0) {
       bytes_read = this->ring_buffer_->read((void *) this->get_buffer_end(), bytes_to_read, ticks_to_wait);
     }
 
@@ -161,7 +161,7 @@ size_t AudioSinkTransferBuffer::transfer_data_to_sink(TickType_t ticks_to_wait,
       bytes_written = this->speaker_->play(this->data_start_, this->available(), ticks_to_wait);
     } else
 #endif
-        if (this->ring_buffer_ != nullptr) {
+        if (this->ring_buffer_.use_count() > 0) {
       bytes_written =
           this->ring_buffer_->write_without_replacement((void *) this->data_start_, this->available(), ticks_to_wait);
     } else if (this->sink_callback_ != nullptr) {
@@ -186,7 +186,7 @@ bool AudioSinkTransferBuffer::has_buffered_data() const {
     return (this->speaker_->has_buffered_data() || (this->available() > 0));
   }
 #endif
-  if (this->ring_buffer_ != nullptr) {
+  if (this->ring_buffer_.use_count() > 0) {
     return ((this->ring_buffer_->available() > 0) || (this->available() > 0));
   }
   return (this->available() > 0);

esphome/components/debug/sensor.py

@@ -23,11 +23,7 @@ from esphome.const import (
 )
 from esphome.types import ConfigType
 
-from . import (  # noqa: F401  pylint: disable=unused-import
-    CONF_DEBUG_ID,
-    FILTER_SOURCE_FILES,
-    DebugComponent,
-)
+from . import CONF_DEBUG_ID, FILTER_SOURCE_FILES, DebugComponent  # noqa: F401  pylint: disable=unused-import
 
 DEPENDENCIES = ["debug"]
 

esphome/components/debug/text_sensor.py

@@ -9,11 +9,7 @@ from esphome.const import (
 )
 from esphome.types import ConfigType
 
-from . import (  # noqa: F401  pylint: disable=unused-import
-    CONF_DEBUG_ID,
-    FILTER_SOURCE_FILES,
-    DebugComponent,
-)
+from . import CONF_DEBUG_ID, FILTER_SOURCE_FILES, DebugComponent  # noqa: F401  pylint: disable=unused-import
 
 DEPENDENCIES = ["debug"]
 

esphome/components/esp32/const.py

@@ -3,18 +3,11 @@ import esphome.codegen as cg
 # Re-exported for the many esp32-side users; defined in esphome.const
 # and esphome.espidf so the upload/logs fast path can use them without
 # importing this package.
-from esphome.const import (  # noqa: F401  # pylint: disable=unused-import
-    KEY_ESP32,
-    KEY_FLASH_SIZE,
-    KEY_IDF_VERSION,
-    KEY_VARIANT,
-)
+from esphome.const import KEY_ESP32, KEY_FLASH_SIZE, KEY_IDF_VERSION, KEY_VARIANT  # noqa: F401  # pylint: disable=unused-import
 
 # Back compat for external components only; in-tree callers import it
 # from esphome.espidf directly.
-from esphome.espidf import (  # noqa: F401  # pylint: disable=unused-import
-    variant_to_idf_target,
-)
+from esphome.espidf import variant_to_idf_target  # noqa: F401  # pylint: disable=unused-import
 
 KEY_BOARD = "board"
 KEY_SDKCONFIG_OPTIONS = "sdkconfig_options"

esphome/components/esphome/ota/ota_esphome.cpp

@@ -41,10 +41,7 @@ const noise::NoiseContext &ESPHomeOTAComponent::noise_context_() const {
 #endif
 static constexpr uint16_t OTA_BLOCK_SIZE = 8192;
 static constexpr uint32_t OTA_SOCKET_TIMEOUT_HANDSHAKE = 20000;  // milliseconds for initial handshake
-// Milliseconds for data transfer. Covers the lwIP retransmit run seen in
-// practice for a lost chunk ack (1.5 + 3 + 6 + 12 + 24 + 48 s); the CLI waits
-// longer (espota2.DATA_PHASE_TIMEOUT) so the device is free before it retries
-static constexpr uint32_t OTA_SOCKET_TIMEOUT_DATA = 105000;
+static constexpr uint32_t OTA_SOCKET_TIMEOUT_DATA = 90000;       // milliseconds for data transfer
 
 // Single-instance pointer — multi-port configs are rejected in final_validate.
 // NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables)

esphome/components/i2s_audio/speaker/i2s_audio_speaker.cpp

@@ -118,24 +118,21 @@ void I2SAudioSpeakerBase::loop() {
         break;
       }
 
-      // Still starting up or winding down from a previous run
-      if ((this->tx_handle_ != nullptr) || (this->speaker_task_handle_ != nullptr)) {
-        break;
-      }
-
       if (this->start_i2s_driver(this->audio_stream_info_) != ESP_OK) {
         ESP_LOGE(TAG, "Driver failed to start; retrying in 1 second");
         this->status_momentary_error("driver-failure", 1000);
         break;
       }
 
-      xTaskCreate(I2SAudioSpeakerBase::speaker_task, "speaker_task", TASK_STACK_SIZE, (void *) this, TASK_PRIORITY,
-                  &this->speaker_task_handle_);
-
       if (this->speaker_task_handle_ == nullptr) {
-        ESP_LOGE(TAG, "Task failed to start, retrying in 1 second");
-        this->status_momentary_error("task-failure", 1000);
-        this->stop_i2s_driver_();  // Stops the driver to return the lock; will be reloaded in next attempt
+        xTaskCreate(I2SAudioSpeakerBase::speaker_task, "speaker_task", TASK_STACK_SIZE, (void *) this, TASK_PRIORITY,
+                    &this->speaker_task_handle_);
+
+        if (this->speaker_task_handle_ == nullptr) {
+          ESP_LOGE(TAG, "Task failed to start, retrying in 1 second");
+          this->status_momentary_error("task-failure", 1000);
+          this->stop_i2s_driver_();  // Stops the driver to return the lock; will be reloaded in next attempt
+        }
       }
       break;
     case speaker::STATE_RUNNING:   // Intentional fallthrough
@@ -221,8 +218,8 @@ size_t I2SAudioSpeakerBase::play(const uint8_t *data, size_t length, TickType_t
 }
 
 bool I2SAudioSpeakerBase::has_buffered_data() const {
-  std::shared_ptr<ring_buffer::RingBuffer> temp_ring_buffer = this->audio_ring_buffer_.lock();
-  if (temp_ring_buffer != nullptr) {
+  if (this->audio_ring_buffer_.use_count() > 0) {
+    std::shared_ptr<ring_buffer::RingBuffer> temp_ring_buffer = this->audio_ring_buffer_.lock();
     return temp_ring_buffer->available() > 0;
   }
   return false;

esphome/components/micro_wake_word/micro_wake_word.cpp

@@ -129,7 +129,7 @@ void MicroWakeWord::setup() {
       return;
     }
     std::shared_ptr<ring_buffer::RingBuffer> temp_ring_buffer = this->ring_buffer_.lock();
-    if (temp_ring_buffer != nullptr) {
+    if (this->ring_buffer_.use_count() > 1) {
       // Producer-only write: never touches consumer state. If the buffer is full, ask the inference task
       // to drain it - reset() is a consumer operation and must run on the inference task's thread.
       // Disable partial writes so audio chunks are either fully accepted or rejected and handled below.
@@ -446,9 +446,9 @@ void MicroWakeWord::loop() {
     xEventGroupClearBits(this->event_group_, EventGroupBits::TASK_STOPPING);
   }
 
-  // Retries on a subsequent loop if the task is still running on the other core
-  if ((event_group_bits & EventGroupBits::TASK_STOPPED) && this->inference_task_.deallocate()) {
+  if ((event_group_bits & EventGroupBits::TASK_STOPPED)) {
     ESP_LOGD(TAG, "Inference task is finished, freeing task resources");
+    this->inference_task_.deallocate();
     xEventGroupClearBits(this->event_group_, ALL_BITS);
     xQueueReset(this->detection_queue_);
     this->set_state_(State::STOPPED);

esphome/components/microphone/microphone_source.h

@@ -48,7 +48,7 @@ class MicrophoneSource final {
   template<typename F> void add_data_callback(F &&data_callback) {
     this->mic_->add_data_callback([this, data_callback](const std::vector<uint8_t> &data) {
       if (this->enabled_ || this->passive_) {
-        if (this->processed_samples_ == nullptr) {
+        if (this->processed_samples_.use_count() == 0) {
           // Create vector if its unused
           this->processed_samples_ = std::make_shared<std::vector<uint8_t>>();
         }

esphome/components/mipi_dsi/mipi_dsi.cpp

@@ -35,8 +35,8 @@ void MipiDsi::setup() {
       .bus_id = 0,  // index from 0, specify the DSI host to use
       .num_data_lanes =
           this->lanes_,  // Number of data lanes to use, can't set a value that exceeds the chip's capability
-      .phy_clk_src = MIPI_DSI_PHY_CLK_SRC_DEFAULT,  // Clock source for the DPHY
-      .lane_bit_rate_mbps = this->lane_bit_rate_,   // Bit rate of the data lanes, in Mbps
+      // phy_clk_src left at 0 to enable runtime auto-select.
+      .lane_bit_rate_mbps = this->lane_bit_rate_,  // Bit rate of the data lanes, in Mbps
   };
   auto err = esp_lcd_new_dsi_bus(&bus_config, &this->bus_handle_);
   if (err != ESP_OK) {

esphome/components/mixer/speaker/mixer_speaker.cpp

@@ -218,7 +218,7 @@ size_t SourceSpeaker::play(const uint8_t *data, size_t length, TickType_t ticks_
   }
   size_t bytes_written = 0;
   std::shared_ptr<ring_buffer::RingBuffer> temp_ring_buffer = this->ring_buffer_.lock();
-  if (temp_ring_buffer != nullptr) {
+  if (temp_ring_buffer.use_count() > 0) {
     // Only write to the ring buffer if the reference is valid
     bytes_written = temp_ring_buffer->write_without_replacement(data, length, ticks_to_wait);
     if (bytes_written > 0) {
@@ -250,14 +250,14 @@ esp_err_t SourceSpeaker::start_() {
   // avoids unnecessary single-frame splices.
   const size_t ring_buffer_size =
       (this->audio_stream_info_.ms_to_bytes(this->buffer_duration_ms_) / bytes_per_frame) * bytes_per_frame;
-  if (this->audio_source_ == nullptr) {
+  if (this->audio_source_.use_count() == 0) {
     std::shared_ptr<ring_buffer::RingBuffer> temp_ring_buffer = this->ring_buffer_.lock();
-    if (temp_ring_buffer == nullptr) {
+    if (!temp_ring_buffer) {
       temp_ring_buffer = ring_buffer::RingBuffer::create(ring_buffer_size);
       this->ring_buffer_ = temp_ring_buffer;
     }
 
-    if (temp_ring_buffer == nullptr) {
+    if (!temp_ring_buffer) {
       return ESP_ERR_NO_MEM;
     }
 
@@ -278,7 +278,7 @@ void SourceSpeaker::stop() { this->send_command_(SOURCE_SPEAKER_COMMAND_STOP); }
 void SourceSpeaker::finish() { this->send_command_(SOURCE_SPEAKER_COMMAND_FINISH); }
 
 bool SourceSpeaker::has_buffered_data() const {
-  return ((this->audio_source_ != nullptr) && this->audio_source_->has_buffered_data());
+  return ((this->audio_source_.use_count() > 0) && this->audio_source_->has_buffered_data());
 }
 
 void SourceSpeaker::set_mute_state(bool mute_state) {
@@ -382,8 +382,8 @@ void MixerSpeaker::loop() {
     ESP_LOGV(TAG, "Stopping");
     xEventGroupClearBits(this->event_group_, MIXER_TASK_STATE_STOPPING);
   }
-  // Retries on a subsequent loop if the task is still running on the other core
-  if ((event_group_bits & MIXER_TASK_STATE_STOPPED) && this->task_.deallocate()) {
+  if (event_group_bits & MIXER_TASK_STATE_STOPPED) {
+    this->task_.deallocate();
     ESP_LOGD(TAG, "Stopped");
     xEventGroupClearBits(this->event_group_, MIXER_TASK_ALL_BITS);
     this->all_stopped_since_ms_ = 0;
@@ -496,7 +496,7 @@ void MixerSpeaker::audio_mixer_task(void *params) {
         if (speaker->is_running() && !speaker->get_pause_state()) {
           // Speaker is running and not paused, so it possibly can provide audio data
           std::shared_ptr<audio::RingBufferAudioSource> audio_source = speaker->get_audio_source().lock();
-          if (audio_source == nullptr) {
+          if (audio_source.use_count() == 0) {
             // No audio source allocated, so skip processing this speaker
             continue;
           }

esphome/components/nextion/display.py

@@ -14,12 +14,7 @@ from esphome.const import (
 )
 from esphome.core import CORE, TimePeriod
 
-from . import (  # noqa: F401  pylint: disable=unused-import
-    FILTER_SOURCE_FILES,
-    Nextion,
-    nextion_ns,
-    nextion_ref,
-)
+from . import FILTER_SOURCE_FILES, Nextion, nextion_ns, nextion_ref  # noqa: F401  pylint: disable=unused-import
 from .base_component import (
     CONF_AUTO_WAKE_ON_TOUCH,
     CONF_COMMAND_SPACING,

esphome/components/noise/__init__.py

@@ -88,12 +88,12 @@ def encryption_schema(config: ConfigType | None) -> ConfigType:
 
 async def to_code(config: ConfigType) -> None:
     cg.add_define("USE_NOISE")
-    cg.add_library("esphome/noise-c", "0.1.26")
+    cg.add_library("esphome/noise-c", "0.1.24")
     # noise-c depends on libsodium, but declaring it here too lets the
     # library manager see the full set up front instead of discovering
     # libsodium only after noise-c has downloaded, so the two can download
     # in parallel. The version must match noise-c's library.json.
-    cg.add_library("esphome/libsodium", "1.10021.8")
+    cg.add_library("esphome/libsodium", "1.10021.6")
     # Enable optimized memzero/memcmp in libsodium instead of volatile byte loops
     cg.add_build_flag("-DHAVE_WEAK_SYMBOLS=1")
     cg.add_build_flag("-DHAVE_INLINE_ASM=1")

esphome/components/resampler/speaker/resampler_speaker.cpp

@@ -153,8 +153,8 @@ void ResamplerSpeaker::loop() {
     ESP_LOGV(TAG, "Stopping");
     xEventGroupClearBits(this->event_group_, ResamplingEventGroupBits::STATE_STOPPING);
   }
-  // Retries on a subsequent loop if the task is still running on the other core
-  if ((event_group_bits & ResamplingEventGroupBits::STATE_STOPPED) && this->task_.deallocate()) {
+  if (event_group_bits & ResamplingEventGroupBits::STATE_STOPPED) {
+    this->task_.deallocate();
     ESP_LOGD(TAG, "Stopped");
     xEventGroupClearBits(this->event_group_, ResamplingEventGroupBits::ALL_BITS);
   }
@@ -235,7 +235,7 @@ size_t ResamplerSpeaker::play(const uint8_t *data, size_t length, TickType_t tic
     bytes_written = this->output_speaker_->play(data, length, ticks_to_wait);
   } else {
     std::shared_ptr<ring_buffer::RingBuffer> temp_ring_buffer = this->ring_buffer_.lock();
-    if (temp_ring_buffer != nullptr) {
+    if (temp_ring_buffer) {
       // Only write to the ring buffer if the reference is valid
       bytes_written = temp_ring_buffer->write_without_replacement(data, length, ticks_to_wait);
     } else {
@@ -299,7 +299,7 @@ bool ResamplerSpeaker::has_buffered_data() const {
   bool has_ring_buffer_data = false;
   if (this->requires_resampling_()) {
     std::shared_ptr<ring_buffer::RingBuffer> temp_ring_buffer = this->ring_buffer_.lock();
-    if (temp_ring_buffer != nullptr) {
+    if (temp_ring_buffer) {
       has_ring_buffer_data = (temp_ring_buffer->available() > 0);
     }
   }
@@ -342,7 +342,7 @@ void ResamplerSpeaker::resample_task(void *params) {
       std::shared_ptr<ring_buffer::RingBuffer> temp_ring_buffer = ring_buffer::RingBuffer::create(
           this_resampler->audio_stream_info_.ms_to_bytes(this_resampler->buffer_duration_ms_));
 
-      if (temp_ring_buffer == nullptr) {
+      if (!temp_ring_buffer) {
         err = ESP_ERR_NO_MEM;
       } else {
         this_resampler->ring_buffer_ = temp_ring_buffer;

esphome/components/sendspin/__init__.py

@@ -30,7 +30,6 @@ CONF_SENDSPIN_ID = "sendspin_id"
 CONF_INITIAL_STATIC_DELAY = "initial_static_delay"
 CONF_FIXED_DELAY = "fixed_delay"
 CONF_DECODE_MEMORY = "decode_memory"
-CONF_CODECS = "codecs"
 
 # Matches ARTWORK_MAX_SLOTS in sendspin-cpp.
 MAX_ARTWORK_SLOTS = 4
@@ -45,20 +44,6 @@ CODEC_FORMAT_OPUS = SendspinCodecFormat.enum("OPUS")
 CODEC_FORMAT_PCM = SendspinCodecFormat.enum("PCM")
 CODEC_FORMAT_UNSUPPORTED = SendspinCodecFormat.enum("UNSUPPORTED")
 
-CODEC_FLAC = "flac"
-CODEC_OPUS = "opus"
-CODEC_PCM = "pcm"
-
-CODECS = {
-    CODEC_FLAC: CODEC_FORMAT_FLAC,
-    CODEC_OPUS: CODEC_FORMAT_OPUS,
-    CODEC_PCM: CODEC_FORMAT_PCM,
-}
-
-# Opus only supports 48 kHz audio, so it is left out of the default list at other rates.
-DEFAULT_CODECS = [CODEC_FLAC, CODEC_OPUS, CODEC_PCM]
-OPUS_SAMPLE_RATE = 48000
-
 SendspinImageFormat = sendspin_library_ns.enum("SendspinImageFormat", is_class=True)
 IMAGE_FORMAT_JPEG = SendspinImageFormat.enum("JPEG")
 IMAGE_FORMAT_PNG = SendspinImageFormat.enum("PNG")
@@ -301,13 +286,16 @@ async def to_code(config: ConfigType) -> None:
     if data.player_support:
         cg.add_define("USE_SENDSPIN_PLAYER", True)
 
-        # Configures the player role. Each configured codec is advertised for 16 bits per sample
-        # mono and stereo at the configured sample rate. The order is a preference order, both for
-        # the codecs themselves and for stereo over mono.
+        # Configures the player role. We always assume support for 16 bits per sample mono and stereo FLAC, Opus, and PCM at the configured sample rate
+        # (with Opus only supported at 48 kHz since that's the only sample rate it supports). Users can configure the specific formats via the Sendspin server
         player_cfg = data.player_config
         sample_rate = player_cfg[CONF_SAMPLE_RATE]
 
-        codecs = player_cfg[CONF_CODECS]
+        # OPUS only supports 48 kHz audio
+        codecs = [CODEC_FORMAT_FLAC]
+        if sample_rate == 48000:
+            codecs.append(CODEC_FORMAT_OPUS)
+        codecs.append(CODEC_FORMAT_PCM)
 
         def _audio_format(codec: MockObj, channels: int) -> cg.StructInitializer:
             return cg.StructInitializer(

esphome/components/sendspin/media_source/__init__.py

@@ -13,16 +13,11 @@ from esphome.cpp_generator import MockObj, TemplateArgsType
 from esphome.types import ConfigType
 
 from .. import (
-    CODEC_OPUS,
-    CODECS,
-    CONF_CODECS,
     CONF_DECODE_MEMORY,
     CONF_FIXED_DELAY,
     CONF_INITIAL_STATIC_DELAY,
     CONF_SENDSPIN_ID,
-    DEFAULT_CODECS,
     MEMORY_LOCATIONS,
-    OPUS_SAMPLE_RATE,
     SendspinHub,
     register_player_config,
     request_controller_support,
@@ -54,32 +49,10 @@ DisableStaticDelayAdjustmentAction = sendspin_ns.class_(
 )
 
 
-def _resolve_codecs(config: ConfigType) -> ConfigType:
-    """Validate the codec preference list, filling in the default when it is not set."""
-    sample_rate = config[CONF_SAMPLE_RATE]
-    if (codecs := config.get(CONF_CODECS)) is None:
-        config[CONF_CODECS] = [
-            codec
-            for codec in DEFAULT_CODECS
-            if codec != CODEC_OPUS or sample_rate == OPUS_SAMPLE_RATE
-        ]
-        return config
-
-    if len(set(codecs)) != len(codecs):
-        raise cv.Invalid("Each codec may only be listed once", path=[CONF_CODECS])
-    if CODEC_OPUS in codecs and sample_rate != OPUS_SAMPLE_RATE:
-        raise cv.Invalid(
-            f"Codec '{CODEC_OPUS}' requires a {CONF_SAMPLE_RATE} of {OPUS_SAMPLE_RATE}",
-            path=[CONF_CODECS],
-        )
-    return config
-
-
 def _register(config: ConfigType) -> ConfigType:
     request_controller_support()
     register_player_config(
         {
-            CONF_CODECS: config[CONF_CODECS],
             CONF_SAMPLE_RATE: config[CONF_SAMPLE_RATE],
             CONF_BUFFER_SIZE: config[CONF_BUFFER_SIZE],
             CONF_INITIAL_STATIC_DELAY: config[CONF_INITIAL_STATIC_DELAY],
@@ -112,13 +85,9 @@ CONFIG_SCHEMA = cv.All(
                 min=16000, max=96000
             ),
             cv.Optional(CONF_DECODE_MEMORY): cv.one_of(*MEMORY_LOCATIONS, lower=True),
-            cv.Optional(CONF_CODECS): cv.All(
-                cv.ensure_list(cv.enum(CODECS, lower=True)), cv.Length(min=1)
-            ),
         }
     ),
     cv.only_on_esp32,
-    _resolve_codecs,
     _register,
 )
 

esphome/components/socket/__init__.py

@@ -187,7 +187,9 @@ async def to_code(config: ConfigType) -> None:
 # for the selected implementation.
 FILTER_SOURCE_FILES = filter_source_files_from_defines(
     {
+        "lwip_raw_common_impl.cpp": "USE_SOCKET_IMPL_LWIP_TCP",
         "lwip_raw_tcp_impl.cpp": "USE_SOCKET_IMPL_LWIP_TCP",
+        "lwip_raw_udp_impl.cpp": "USE_SOCKET_IMPL_LWIP_TCP",
         "bsd_sockets_impl.cpp": "USE_SOCKET_IMPL_BSD_SOCKETS",
         "lwip_sockets_impl.cpp": "USE_SOCKET_IMPL_LWIP_SOCKETS",
     }

esphome/components/socket/bsd_sockets_impl.h

@@ -144,6 +144,9 @@ class BSDSocketImpl {
 
   int get_fd() const { return this->fd_; }
 
+  /// UDP rx drop counter parity with LWIPRawUDPImpl; drops are not counted here.
+  uint16_t get_rx_dropped() const { return 0; }
+
  protected:
   // fd_ < 0 means "not open" — used both pre-open (initial state) and post-close. This
   // replaces a separate closed_ flag: close() sets fd_ = -1 after ::close(), and the

esphome/components/socket/headers.h

@@ -20,6 +20,16 @@
 
 #define IPPROTO_IP 0
 #define IPPROTO_TCP 6
+#define IPPROTO_UDP 17
+
+#define IP_ADD_MEMBERSHIP 3
+#define IP_DROP_MEMBERSHIP 4
+
+// NOLINTNEXTLINE(readability-identifier-naming)
+struct ip_mreq {
+  struct in_addr imr_multiaddr;
+  struct in_addr imr_interface;
+};
 
 #if LWIP_IPV6
 #define AF_INET6 10

esphome/components/socket/lwip_raw_common_impl.cpp

@@ -0,0 +1,109 @@
+#include "lwip_raw_common_impl.h"
+#include "esphome/core/defines.h"
+
+#ifdef USE_SOCKET_IMPL_LWIP_TCP
+
+#include <cerrno>
+#include <cstring>
+
+namespace esphome::socket {
+
+int lwip_ip_to_sockaddr(sa_family_t family, const ip_addr_t *ip, uint16_t port_host, struct sockaddr *name,
+                        socklen_t *addrlen) {
+  if (family == AF_INET) {
+    if (*addrlen < sizeof(struct sockaddr_in)) {
+      errno = EINVAL;
+      return -1;
+    }
+    auto *addr = reinterpret_cast<struct sockaddr_in *>(name);
+    addr->sin_family = AF_INET;
+    *addrlen = addr->sin_len = sizeof(struct sockaddr_in);
+    addr->sin_port = htons(port_host);
+    inet_addr_from_ip4addr(&addr->sin_addr, ip_2_ip4(ip));
+    return 0;
+  }
+#if LWIP_IPV6
+  if (family == AF_INET6) {
+    if (*addrlen < sizeof(struct sockaddr_in6)) {
+      errno = EINVAL;
+      return -1;
+    }
+    auto *addr = reinterpret_cast<struct sockaddr_in6 *>(name);
+    addr->sin6_family = AF_INET6;
+    *addrlen = addr->sin6_len = sizeof(struct sockaddr_in6);
+    addr->sin6_port = htons(port_host);
+    // AF_INET6 sockets may receive IPv4 packets; convert to IPv4-mapped IPv6.
+    if (IP_IS_V4(ip)) {
+      ip_addr_t mapped;
+      ip4_2_ipv4_mapped_ipv6(ip_2_ip6(&mapped), ip_2_ip4(ip));
+      inet6_addr_from_ip6addr(&addr->sin6_addr, ip_2_ip6(&mapped));
+    } else {
+      inet6_addr_from_ip6addr(&addr->sin6_addr, ip_2_ip6(ip));
+    }
+    return 0;
+  }
+#endif
+  errno = EAFNOSUPPORT;
+  return -1;
+}
+
+bool sockaddr_to_lwip(const struct sockaddr *addr, socklen_t addrlen, ip_addr_t *ip, uint16_t *port) {
+  // headers.h defines sockaddr and sockaddr_in with the same size, so this covers AF_INET
+  if (addrlen < sizeof(struct sockaddr))
+    return false;
+  // Zero the whole struct — the IPv6 zone byte would otherwise be stack garbage
+  memset(ip, 0, sizeof(*ip));
+  if (addr->sa_family == AF_INET) {
+    auto *addr4 = reinterpret_cast<const sockaddr_in *>(addr);
+    *port = ntohs(addr4->sin_port);
+    IP_SET_TYPE_VAL(*ip, IPADDR_TYPE_V4);
+    ip_2_ip4(ip)->addr = addr4->sin_addr.s_addr;
+    return true;
+  }
+#if LWIP_IPV6
+  if (addr->sa_family == AF_INET6) {
+    if (addrlen < sizeof(sockaddr_in6))
+      return false;
+    auto *addr6 = reinterpret_cast<const sockaddr_in6 *>(addr);
+    *port = ntohs(addr6->sin6_port);
+    IP_SET_TYPE_VAL(*ip, IPADDR_TYPE_V6);
+    memcpy(&ip_2_ip6(ip)->addr, &addr6->sin6_addr.un.u8_addr, 16);
+    // Unmap ::ffff:a.b.c.d so replies to recvfrom addresses route as IPv4
+    if (ip6_addr_isipv4mappedipv6(ip_2_ip6(ip))) {
+      unmap_ipv4_mapped_ipv6(ip_2_ip4(ip), ip_2_ip6(ip));
+      IP_SET_TYPE_VAL(*ip, IPADDR_TYPE_V4);
+    }
+    return true;
+  }
+#endif
+  return false;
+}
+
+bool sockaddr_to_lwip_bind(sa_family_t family, const struct sockaddr *addr, socklen_t addrlen, ip_addr_t *ip,
+                           uint16_t *port) {
+  if (!sockaddr_to_lwip(addr, addrlen, ip, port))
+    return false;
+#if LWIP_IPV6
+  // Only promote wildcard binds — a specific address must keep filtering
+  if (family == AF_INET6 && ip_addr_isany_val(*ip))
+    IP_SET_TYPE_VAL(*ip, IPADDR_TYPE_ANY);
+#endif
+  return true;
+}
+
+int lwip_bind_err(err_t err) {
+  if (err == ERR_OK)
+    return 0;
+  if (err == ERR_USE) {
+    errno = EADDRINUSE;
+  } else if (err == ERR_VAL) {
+    errno = EINVAL;
+  } else {
+    errno = EIO;
+  }
+  return -1;
+}
+
+}  // namespace esphome::socket
+
+#endif  // USE_SOCKET_IMPL_LWIP_TCP

esphome/components/socket/lwip_raw_common_impl.h

@@ -0,0 +1,53 @@
+#pragma once
+#include "esphome/core/defines.h"
+
+#ifdef USE_SOCKET_IMPL_LWIP_TCP
+
+#include "headers.h"
+#include "lwip/ip.h"
+
+namespace esphome::socket {
+
+// ---- LWIP thread safety ----
+//
+// On RP2040 (Pico W), arduino-pico sets PICO_CYW43_ARCH_THREADSAFE_BACKGROUND=1.
+// This means lwip callbacks (recv_fn, accept_fn, err_fn) run from a low-priority
+// user IRQ context, not the main loop (see low_priority_irq_handler() in pico-sdk
+// async_context_threadsafe_background.c). They can preempt main-loop code at any point.
+//
+// Without locking, this causes race conditions between recv_fn and read() on the
+// shared rx_buf_ pbuf chain — recv_fn calls pbuf_cat() while read() is freeing
+// nodes, leading to use-after-free and infinite-loop crashes. See esphome#10681.
+//
+// On ESP8266, lwip callbacks run from the SYS context which cooperates with user
+// code (CONT context) — they never preempt each other, so no locking is needed.
+//
+// esphome::LwIPLock is the platform-provided RAII guard (see helpers.h/helpers.cpp).
+// On RP2040, it acquires cyw43_arch_lwip_begin/end (WiFi) or ethernet_arch_lwip_begin/end
+// (Ethernet). On ESP8266, it's a no-op.
+//
+// Each .cpp file that needs locking defines its own LWIP_LOCK() macro:
+//   #define LWIP_LOCK() esphome::LwIPLock lwip_lock_guard
+// This is a per-TU convenience macro, not defined here to avoid macro leaking.
+
+/// Convert lwip ip_addr_t + host-order port to sockaddr, based on the socket's address family.
+/// TCP callers pass ntohs(pcb port) to preserve historical getpeername/getsockname output.
+int lwip_ip_to_sockaddr(sa_family_t family, const ip_addr_t *ip, uint16_t port_host, struct sockaddr *name,
+                        socklen_t *addrlen);
+
+/// Convert sockaddr to lwip ip_addr_t and host-order port.
+/// For IPv6, sets type to IPADDR_TYPE_V6 — correct for sendto destinations.
+/// Bind paths must use sockaddr_to_lwip_bind() instead.
+bool sockaddr_to_lwip(const struct sockaddr *addr, socklen_t addrlen, ip_addr_t *ip, uint16_t *port);
+
+/// sockaddr_to_lwip variant for bind: promotes AF_INET6 sockets to
+/// IPADDR_TYPE_ANY so they accept both IPv4 and IPv6 (dual-stack).
+bool sockaddr_to_lwip_bind(sa_family_t family, const struct sockaddr *addr, socklen_t addrlen, ip_addr_t *ip,
+                           uint16_t *port);
+
+/// Map lwip bind error to errno. Returns 0 on success, -1 on error with errno set.
+int lwip_bind_err(err_t err);
+
+}  // namespace esphome::socket
+
+#endif  // USE_SOCKET_IMPL_LWIP_TCP

esphome/components/socket/lwip_raw_tcp_impl.cpp

@@ -10,6 +10,7 @@
 #include "esphome/core/helpers.h"
 #include "esphome/core/wake.h"
 #include "esphome/core/log.h"
+#include "lwip_raw_common_impl.h"
 
 #ifdef USE_OTA_PLATFORM_ESPHOME
 extern "C" void esphome_wake_ota_component_any_context();
@@ -24,23 +25,9 @@ extern "C" void esphome_wake_ota_component_any_context();
 
 namespace esphome::socket {
 
-// ---- LWIP thread safety ----
-//
-// On RP2040 (Pico W), arduino-pico sets PICO_CYW43_ARCH_THREADSAFE_BACKGROUND=1.
-// This means lwip callbacks (recv_fn, accept_fn, err_fn) run from a low-priority
-// user IRQ context, not the main loop (see low_priority_irq_handler() in pico-sdk
-// async_context_threadsafe_background.c). They can preempt main-loop code at any point.
-//
-// Without locking, this causes race conditions between recv_fn and read() on the
-// shared rx_buf_ pbuf chain — recv_fn calls pbuf_cat() while read() is freeing
-// nodes, leading to use-after-free and infinite-loop crashes. See esphome#10681.
-//
-// On ESP8266, lwip callbacks run from the SYS context which cooperates with user
-// code (CONT context) — they never preempt each other, so no locking is needed.
-//
-// esphome::LwIPLock is the platform-provided RAII guard (see helpers.h/helpers.cpp).
-// On RP2040, it acquires cyw43_arch_lwip_begin/end (WiFi) or ethernet_arch_lwip_begin/end
-// (Ethernet). On ESP8266, it's a no-op.
+// LWIP thread safety — see lwip_raw_common_impl.h for full explanation.
+// esphome::LwIPLock is the platform-provided RAII guard.
+// On RP2040, it acquires cyw43_arch_lwip_begin/end. On ESP8266, it's a no-op.
 #define LWIP_LOCK() esphome::LwIPLock lwip_lock_guard  // NOLINT
 
 static const char *const TAG = "socket";
@@ -112,59 +99,14 @@ int LWIPRawCommon::bind(const struct sockaddr *name, socklen_t addrlen) {
     return -1;
   }
   ip_addr_t ip;
-  in_port_t port;
-#if LWIP_IPV6
-  if (this->family_ == AF_INET) {
-    if (addrlen < sizeof(sockaddr_in)) {
-      errno = EINVAL;
-      return -1;
-    }
-    auto *addr4 = reinterpret_cast<const sockaddr_in *>(name);
-    port = ntohs(addr4->sin_port);
-    ip.type = IPADDR_TYPE_V4;
-    ip.u_addr.ip4.addr = addr4->sin_addr.s_addr;
-    LWIP_LOG("tcp_bind(%p ip=%s port=%u)", this->pcb_, ip4addr_ntoa(&ip.u_addr.ip4), port);
-  } else if (this->family_ == AF_INET6) {
-    if (addrlen < sizeof(sockaddr_in6)) {
-      errno = EINVAL;
-      return -1;
-    }
-    auto *addr6 = reinterpret_cast<const sockaddr_in6 *>(name);
-    port = ntohs(addr6->sin6_port);
-    ip.type = IPADDR_TYPE_ANY;
-    memcpy(&ip.u_addr.ip6.addr, &addr6->sin6_addr.un.u8_addr, 16);
-    LWIP_LOG("tcp_bind(%p ip=%s port=%u)", this->pcb_, ip6addr_ntoa(&ip.u_addr.ip6), port);
-  } else {
+  uint16_t port;
+  if (!sockaddr_to_lwip_bind(this->family_, name, addrlen, &ip, &port)) {
     errno = EINVAL;
     return -1;
   }
-#else
-  if (this->family_ != AF_INET) {
-    errno = EINVAL;
-    return -1;
-  }
-  auto *addr4 = reinterpret_cast<const sockaddr_in *>(name);
-  port = ntohs(addr4->sin_port);
-  ip.addr = addr4->sin_addr.s_addr;
-  LWIP_LOG("tcp_bind(%p ip=%u port=%u)", this->pcb_, ip.addr, port);
-#endif
   err_t err = tcp_bind(this->pcb_, &ip, port);
-  if (err == ERR_USE) {
-    LWIP_LOG("  -> err ERR_USE");
-    errno = EADDRINUSE;
-    return -1;
-  }
-  if (err == ERR_VAL) {
-    LWIP_LOG("  -> err ERR_VAL");
-    errno = EINVAL;
-    return -1;
-  }
-  if (err != ERR_OK) {
-    LWIP_LOG("  -> err %d", err);
-    errno = EIO;
-    return -1;
-  }
-  return 0;
+  LWIP_LOG("  -> err %d", err);
+  return lwip_bind_err(err);
 }
 
 int LWIPRawCommon::close() {
@@ -349,43 +291,8 @@ int LWIPRawCommon::setsockopt(int level, int optname, const void *optval, sockle
 }
 
 int LWIPRawCommon::ip2sockaddr_(ip_addr_t *ip, uint16_t port, struct sockaddr *name, socklen_t *addrlen) {
-  if (this->family_ == AF_INET) {
-    if (*addrlen < sizeof(struct sockaddr_in)) {
-      errno = EINVAL;
-      return -1;
-    }
-
-    struct sockaddr_in *addr = reinterpret_cast<struct sockaddr_in *>(name);
-    addr->sin_family = AF_INET;
-    *addrlen = addr->sin_len = sizeof(struct sockaddr_in);
-    addr->sin_port = port;
-    inet_addr_from_ip4addr(&addr->sin_addr, ip_2_ip4(ip));
-    return 0;
-  }
-#if LWIP_IPV6
-  else if (this->family_ == AF_INET6) {
-    if (*addrlen < sizeof(struct sockaddr_in6)) {
-      errno = EINVAL;
-      return -1;
-    }
-
-    struct sockaddr_in6 *addr = reinterpret_cast<struct sockaddr_in6 *>(name);
-    addr->sin6_family = AF_INET6;
-    *addrlen = addr->sin6_len = sizeof(struct sockaddr_in6);
-    addr->sin6_port = port;
-
-    // AF_INET6 sockets are bound to IPv4 as well, so we may encounter IPv4 addresses that must be converted to IPv6.
-    if (IP_IS_V4(ip)) {
-      ip_addr_t mapped;
-      ip4_2_ipv4_mapped_ipv6(ip_2_ip6(&mapped), ip_2_ip4(ip));
-      inet6_addr_from_ip6addr(&addr->sin6_addr, ip_2_ip6(&mapped));
-    } else {
-      inet6_addr_from_ip6addr(&addr->sin6_addr, ip_2_ip6(ip));
-    }
-    return 0;
-  }
-#endif
-  return -1;
+  // lwip pcb ports are host order; ntohs preserves historical byte-swapped sin_port output
+  return lwip_ip_to_sockaddr(this->family_, ip, ntohs(port), name, addrlen);
 }
 
 // ---- LWIPRawImpl methods ----
@@ -887,11 +794,11 @@ err_t LWIPRawListenImpl::accept_fn_(struct tcp_pcb *newpcb, err_t err) {
   return ERR_OK;
 }
 
-// ---- Factory functions ----
+// ---- TCP Factory functions ----
 
 std::unique_ptr<Socket> socket(int domain, int type, int protocol) {
   if (type != SOCK_STREAM) {
-    ESP_LOGE(TAG, "UDP sockets not supported on this platform, use WiFiUDP");
+    ESP_LOGE(TAG, "Use socket_udp() for UDP sockets on this platform");
     errno = EPROTOTYPE;
     return nullptr;
   }
@@ -911,7 +818,7 @@ std::unique_ptr<Socket> socket_loop_monitored(int domain, int type, int protocol
 
 std::unique_ptr<ListenSocket> socket_listen(int domain, int type, int protocol) {
   if (type != SOCK_STREAM) {
-    ESP_LOGE(TAG, "UDP sockets not supported on this platform, use WiFiUDP");
+    ESP_LOGE(TAG, "Use socket_udp() for UDP sockets on this platform");
     errno = EPROTOTYPE;
     return nullptr;
   }

esphome/components/socket/lwip_raw_udp_impl.cpp

@@ -0,0 +1,328 @@
+#include "socket.h"
+#include "esphome/core/defines.h"
+
+#ifdef USE_SOCKET_IMPL_LWIP_TCP
+
+#include <cerrno>
+#include <cstring>
+
+#include "esphome/core/helpers.h"
+#include "esphome/core/log.h"
+#include "esphome/core/wake.h"
+#include "lwip_raw_common_impl.h"
+
+#include "lwip/igmp.h"
+#include "lwip/pbuf.h"
+#include "lwip/udp.h"
+
+namespace esphome::socket {
+
+// LWIP thread safety — see lwip_raw_common_impl.h for full explanation.
+// esphome::LwIPLock is the platform-provided RAII guard.
+// On RP2040, it acquires cyw43_arch_lwip_begin/end. On ESP8266, it's a no-op.
+#define LWIP_LOCK() esphome::LwIPLock lwip_lock_guard  // NOLINT
+
+// ---- LWIPRawUDPSendImpl (send-only) methods ----
+
+LWIPRawUDPSendImpl::~LWIPRawUDPSendImpl() {
+  // Guard avoids acquiring the lwip lock when already closed
+  if (this->pcb_ != nullptr)
+    this->close();
+}
+
+int LWIPRawUDPSendImpl::bind(const struct sockaddr *name, socklen_t addrlen) {
+  LWIP_LOCK();
+  if (this->pcb_ == nullptr) {
+    errno = EBADF;
+    return -1;
+  }
+  if (name == nullptr) {
+    errno = EINVAL;
+    return -1;
+  }
+  ip_addr_t ip;
+  uint16_t port;
+  if (!sockaddr_to_lwip_bind(this->family_, name, addrlen, &ip, &port)) {
+    errno = EINVAL;
+    return -1;
+  }
+  return lwip_bind_err(udp_bind(this->pcb_, &ip, port));
+}
+
+int LWIPRawUDPSendImpl::close() {
+  LWIP_LOCK();
+  return this->close_internal_locked_();
+}
+
+int LWIPRawUDPSendImpl::close_internal_locked_() {
+  // Caller must hold LWIP_LOCK
+  if (this->pcb_ == nullptr) {
+    errno = EBADF;
+    return -1;
+  }
+  udp_remove(this->pcb_);
+  this->pcb_ = nullptr;
+  return 0;
+}
+
+int LWIPRawUDPSendImpl::ip2sockaddr_(const ip_addr_t *ip, uint16_t port, struct sockaddr *name, socklen_t *addrlen) {
+  // UDP recv callback provides port in host byte order
+  return lwip_ip_to_sockaddr(this->family_, ip, port, name, addrlen);
+}
+
+ssize_t LWIPRawUDPSendImpl::sendto(const void *buf, size_t len, int flags, const struct sockaddr *dest_addr,
+                                   socklen_t addrlen) {
+  (void) flags;  // Flags (MSG_DONTWAIT, etc.) are ignored; raw lwip is always non-blocking
+  if (buf == nullptr || dest_addr == nullptr) {
+    errno = EINVAL;
+    return -1;
+  }
+
+  // pbuf_alloc takes u16_t length; reject oversized packets
+  if (len > UINT16_MAX) {
+    errno = EMSGSIZE;
+    return -1;
+  }
+
+  ip_addr_t dst_ip;
+  uint16_t dst_port;
+  if (!sockaddr_to_lwip(dest_addr, addrlen, &dst_ip, &dst_port)) {
+    errno = EINVAL;
+    return -1;
+  }
+
+  LWIP_LOCK();
+  if (this->pcb_ == nullptr) {
+    errno = EBADF;
+    return -1;
+  }
+
+  // Allocate pbuf and copy data
+  struct pbuf *pb = pbuf_alloc(PBUF_TRANSPORT, (uint16_t) len, PBUF_RAM);
+  if (pb == nullptr) {
+    errno = ENOMEM;
+    return -1;
+  }
+  memcpy(pb->payload, buf, len);
+
+  err_t err = udp_sendto(this->pcb_, pb, &dst_ip, dst_port);
+  pbuf_free(pb);
+
+  if (err != ERR_OK) {
+    errno = err == ERR_MEM ? ENOMEM : EIO;
+    return -1;
+  }
+  return (ssize_t) len;
+}
+
+int LWIPRawUDPSendImpl::setsockopt(int level, int optname, const void *optval, socklen_t optlen) {
+  LWIP_LOCK();
+  if (this->pcb_ == nullptr) {
+    errno = EBADF;
+    return -1;
+  }
+  if (level == SOL_SOCKET && optname == SO_REUSEADDR) {
+    if (optval == nullptr || optlen < sizeof(int)) {
+      errno = EINVAL;
+      return -1;
+    }
+    // Effective only where lwip is built with SO_REUSE=1 (ESP8266 yes, RP2040 currently no)
+    if (*reinterpret_cast<const int *>(optval)) {
+      ip_set_option(this->pcb_, SOF_REUSEADDR);
+    } else {
+      ip_reset_option(this->pcb_, SOF_REUSEADDR);
+    }
+    return 0;
+  }
+  if (level == SOL_SOCKET && optname == SO_BROADCAST) {
+    if (optval == nullptr || optlen < sizeof(int)) {
+      errno = EINVAL;
+      return -1;
+    }
+    int val = *reinterpret_cast<const int *>(optval);
+    if (val) {
+      ip_set_option(this->pcb_, SOF_BROADCAST);
+    } else {
+      ip_reset_option(this->pcb_, SOF_BROADCAST);
+    }
+    return 0;
+  }
+  if (level == IPPROTO_IP && (optname == IP_ADD_MEMBERSHIP || optname == IP_DROP_MEMBERSHIP)) {
+    if (optval == nullptr || optlen < sizeof(struct ip_mreq)) {
+      errno = EINVAL;
+      return -1;
+    }
+    auto *mreq = reinterpret_cast<const struct ip_mreq *>(optval);
+    ip4_addr_t multiaddr{mreq->imr_multiaddr.s_addr};
+    ip4_addr_t ifaddr{mreq->imr_interface.s_addr};
+    err_t err =
+        optname == IP_ADD_MEMBERSHIP ? igmp_joingroup(&ifaddr, &multiaddr) : igmp_leavegroup(&ifaddr, &multiaddr);
+    if (err != ERR_OK) {
+      errno = EIO;
+      return -1;
+    }
+    return 0;
+  }
+  errno = ENOPROTOOPT;
+  return -1;
+}
+
+int LWIPRawUDPSendImpl::getsockopt(int level, int optname, void *optval, socklen_t *optlen) {
+  LWIP_LOCK();
+  if (this->pcb_ == nullptr) {
+    errno = EBADF;
+    return -1;
+  }
+  if (level == SOL_SOCKET && optname == SO_REUSEADDR) {
+    if (optval == nullptr || optlen == nullptr || *optlen < sizeof(int)) {
+      errno = EINVAL;
+      return -1;
+    }
+    *reinterpret_cast<int *>(optval) = ip_get_option(this->pcb_, SOF_REUSEADDR) ? 1 : 0;
+    *optlen = sizeof(int);
+    return 0;
+  }
+  errno = ENOPROTOOPT;
+  return -1;
+}
+
+int LWIPRawUDPSendImpl::setblocking(bool blocking) {
+  if (blocking) {
+    // blocking operation not supported on raw lwip
+    errno = EINVAL;
+    return -1;
+  }
+  return 0;
+}
+
+// ---- LWIPRawUDPImpl methods ----
+
+LWIPRawUDPImpl::LWIPRawUDPImpl(sa_family_t family, struct udp_pcb *pcb) : LWIPRawUDPSendImpl(family, pcb) {
+  // Registered here (not in bind) so unbound client sockets can receive replies
+  udp_recv(this->pcb_, LWIPRawUDPImpl::s_recv_fn, this);
+}
+
+LWIPRawUDPImpl::~LWIPRawUDPImpl() {
+  // Flush rx queue and unregister callback before base destructor removes pcb
+  if (this->pcb_ != nullptr)
+    this->close();
+}
+
+int LWIPRawUDPImpl::close() {
+  LWIP_LOCK();
+  // Unregister recv callback before removing pcb
+  if (this->pcb_ != nullptr) {
+    udp_recv(this->pcb_, nullptr, nullptr);
+  }
+  // Flush queued rx packets; slots within rx_count_ always hold a live pbuf
+  for (; this->rx_count_ > 0; this->rx_count_--) {
+    pbuf_free(this->rx_queue_[this->rx_read_idx_].pb);
+    this->rx_read_idx_ = (this->rx_read_idx_ + 1) & UDP_RX_MASK;
+  }
+  // close_internal_locked_() returns EBADF if already closed, which is fine from destructor
+  return this->close_internal_locked_();
+}
+
+ssize_t LWIPRawUDPImpl::read(void *buf, size_t len) { return this->recvfrom(buf, len, nullptr, nullptr); }
+
+ssize_t LWIPRawUDPImpl::recvfrom(void *buf, size_t len, struct sockaddr *src_addr, socklen_t *addrlen) {
+  if (buf == nullptr && len > 0) {
+    errno = EINVAL;
+    return -1;
+  }
+  LWIP_LOCK();
+  if (this->pcb_ == nullptr) {
+    errno = EBADF;
+    return -1;
+  }
+  if (this->rx_count_ == 0) {
+    errno = EWOULDBLOCK;
+    return -1;
+  }
+
+  auto &pkt = this->rx_queue_[this->rx_read_idx_];
+  // On address conversion failure, still consume the packet — the failure is
+  // deterministic (family_ and *addrlen), so keeping it would wedge the queue
+  ssize_t ret = -1;
+  if (src_addr == nullptr || addrlen == nullptr ||
+      this->ip2sockaddr_(&pkt.src_addr, pkt.src_port, src_addr, addrlen) == 0) {
+    ret = (ssize_t) std::min(len, (size_t) pkt.pb->tot_len);
+    pbuf_copy_partial(pkt.pb, buf, ret, 0);
+  }
+  pbuf_free(pkt.pb);
+  this->rx_read_idx_ = (this->rx_read_idx_ + 1) & UDP_RX_MASK;
+  this->rx_count_--;
+  return ret;
+}
+
+void LWIPRawUDPImpl::s_recv_fn(void *arg, struct udp_pcb *pcb, struct pbuf *p, const ip_addr_t *addr, u16_t port) {
+  auto *self = reinterpret_cast<LWIPRawUDPImpl *>(arg);
+  self->recv_fn_(p, addr, port);
+}
+
+// LWIP CALLBACK — runs from IRQ context on RP2040 (low-priority user IRQ).
+// No heap allocation allowed — malloc is not IRQ-safe (see #14687).
+// No LWIP_LOCK() needed — lwip core already holds the async_context lock.
+void LWIPRawUDPImpl::recv_fn_(struct pbuf *p, const ip_addr_t *addr, u16_t port) {
+  if (p == nullptr)
+    return;
+
+  // Check if queue is full
+  if (this->rx_count_ >= UDP_RX_QUEUE_SIZE) {
+    // Drop packet — queue full. Can't log from IRQ context, so count it
+    // (saturating) for consumers to surface via get_rx_dropped().
+    if (this->rx_dropped_ != UINT16_MAX)
+      this->rx_dropped_++;
+    pbuf_free(p);
+    return;
+  }
+
+  // Enqueue the packet
+  uint8_t write_idx = (this->rx_read_idx_ + this->rx_count_) & UDP_RX_MASK;
+  auto &slot = this->rx_queue_[write_idx];
+  slot.pb = p;
+  slot.src_addr = *addr;
+  slot.src_port = port;
+  this->rx_count_++;
+
+  esphome::wake_loop_any_context();
+}
+
+// ---- UDP Factory functions ----
+
+static struct udp_pcb *new_udp_pcb(int domain) {
+#if LWIP_IPV6
+  return udp_new_ip_type(domain == AF_INET6 ? IPADDR_TYPE_ANY : IPADDR_TYPE_V4);
+#else
+  return udp_new();
+#endif
+}
+
+std::unique_ptr<UDPSendSocket> socket_udp_send(int domain, int protocol) {
+  (void) protocol;  // Raw lwip UDP ignores protocol; kept for API compatibility
+  LWIP_LOCK();
+  auto *pcb = new_udp_pcb(domain);
+  if (pcb == nullptr) {
+    errno = ENOMEM;
+    return nullptr;
+  }
+  return make_unique<LWIPRawUDPSendImpl>((sa_family_t) domain, pcb);
+}
+
+std::unique_ptr<UDPSocket> socket_udp(int domain, int protocol) {
+  (void) protocol;  // Raw lwip UDP ignores protocol; kept for API compatibility
+  LWIP_LOCK();
+  auto *pcb = new_udp_pcb(domain);
+  if (pcb == nullptr) {
+    errno = ENOMEM;
+    return nullptr;
+  }
+  // Ctor registers the recv callback under the lock held here
+  return make_unique<LWIPRawUDPImpl>((sa_family_t) domain, pcb);
+}
+
+#undef LWIP_LOCK
+
+}  // namespace esphome::socket
+
+#endif  // USE_SOCKET_IMPL_LWIP_TCP

esphome/components/socket/lwip_raw_udp_impl.h

@@ -0,0 +1,113 @@
+#pragma once
+#include "esphome/core/defines.h"
+
+#ifdef USE_SOCKET_IMPL_LWIP_TCP
+
+#include <array>
+#include <cstdint>
+
+#include "headers.h"
+#include "lwip/ip.h"
+#include "lwip/udp.h"
+
+namespace esphome::socket {
+
+/// Send-only UDP socket implementation for LWIP raw API.
+/// Non-virtual, concrete type. Uses lwip/udp.h raw API.
+/// No receive capability — use LWIPRawUDPImpl for sockets that need to receive.
+class LWIPRawUDPSendImpl {
+ public:
+  /// The pcb is allocated by the factory (like the TCP impl); never null here.
+  LWIPRawUDPSendImpl(sa_family_t family, struct udp_pcb *pcb) : pcb_(pcb), family_(family) {}
+  ~LWIPRawUDPSendImpl();
+  LWIPRawUDPSendImpl(const LWIPRawUDPSendImpl &) = delete;
+  LWIPRawUDPSendImpl &operator=(const LWIPRawUDPSendImpl &) = delete;
+
+  int bind(const struct sockaddr *name, socklen_t addrlen);
+  int close();
+
+  /// Send a UDP packet to the specified destination.
+  ssize_t sendto(const void *buf, size_t len, int flags, const struct sockaddr *dest_addr, socklen_t addrlen);
+
+  int setsockopt(int level, int optname, const void *optval, socklen_t optlen);
+  int getsockopt(int level, int optname, void *optval, socklen_t *optlen);
+
+  int setblocking(bool blocking);
+
+  bool ready() const { return false; }
+  int get_fd() const { return -1; }
+
+ protected:
+  /// Convert lwip ip_addr_t and port to sockaddr.
+  int ip2sockaddr_(const ip_addr_t *ip, uint16_t port, struct sockaddr *name, socklen_t *addrlen);
+
+  /// Shared close logic — removes the udp pcb. Caller must hold LWIP_LOCK.
+  int close_internal_locked_();
+
+  struct udp_pcb *pcb_;
+  sa_family_t family_;
+};
+
+/// UDP socket with receive support for LWIP raw API.
+/// Extends LWIPRawUDPSendImpl with a fixed-size ring buffer for incoming packets.
+/// Inheritance is private (base dtor is non-virtual; converting to a base
+/// pointer would leak queued pbufs on destruction).
+class LWIPRawUDPImpl : private LWIPRawUDPSendImpl {
+ public:
+  /// Caller (the factory) must hold the lwip lock; registers the recv callback.
+  LWIPRawUDPImpl(sa_family_t family, struct udp_pcb *pcb);
+  ~LWIPRawUDPImpl();
+
+  using LWIPRawUDPSendImpl::bind;
+  using LWIPRawUDPSendImpl::get_fd;
+  using LWIPRawUDPSendImpl::getsockopt;
+  using LWIPRawUDPSendImpl::sendto;
+  using LWIPRawUDPSendImpl::setblocking;
+  using LWIPRawUDPSendImpl::setsockopt;
+
+  /// Close the socket, flushing any queued rx packets first.
+  int close();
+
+  /// Read the next queued packet, discarding source address info.
+  /// If buf is smaller than the packet, data is silently truncated (returns bytes copied).
+  /// Note: unlike POSIX MSG_TRUNC, this does not return the original packet length on truncation.
+  ssize_t read(void *buf, size_t len);
+  /// Read the next queued packet and return the source address.
+  /// If buf is smaller than the packet, data is silently truncated (returns bytes copied).
+  /// Note: unlike POSIX MSG_TRUNC, this does not return the original packet length on truncation.
+  ssize_t recvfrom(void *buf, size_t len, struct sockaddr *src_addr, socklen_t *addrlen);
+
+  /// Returns true if there are packets available to read.
+  /// Intentionally unlocked — same rationale as LWIPRawImpl::ready().
+  bool ready() const { return this->rx_count_ > 0; }
+
+  /// Number of packets dropped because the rx queue was full (saturating).
+  uint16_t get_rx_dropped() const { return this->rx_dropped_; }
+
+ protected:
+  static void s_recv_fn(void *arg, struct udp_pcb *pcb, struct pbuf *p, const ip_addr_t *addr, u16_t port);
+  void recv_fn_(struct pbuf *p, const ip_addr_t *addr, u16_t port);
+
+  /// Ring buffer for received UDP packets.
+  /// Both producer (recv callback) and consumer (main loop) are serialized by the
+  /// lwip lock — the callback runs under lwip core lock, and consumer methods hold
+  /// LWIP_LOCK(). All 4 slots are usable (no wasted slot for full/empty distinction).
+  /// No heap allocation in the recv callback — packets are dropped if the queue is full.
+  static constexpr uint8_t UDP_RX_QUEUE_SIZE = 4;
+  static constexpr uint8_t UDP_RX_MASK = UDP_RX_QUEUE_SIZE - 1;
+  static_assert((UDP_RX_QUEUE_SIZE & UDP_RX_MASK) == 0, "UDP_RX_QUEUE_SIZE must be power of 2");
+  // Fields are written by recv_fn_ before rx_count_ makes a slot visible
+  struct UDPRxPacket {
+    ip_addr_t src_addr;
+    struct pbuf *pb;
+    uint16_t src_port;
+  };
+  std::array<UDPRxPacket, UDP_RX_QUEUE_SIZE> rx_queue_{};
+  uint16_t rx_dropped_{0};
+  uint8_t rx_read_idx_{0};
+  uint8_t rx_count_{0};
+};
+
+}  // namespace esphome::socket
+
+#endif  // USE_SOCKET_IMPL_LWIP_TCP

esphome/components/socket/lwip_sockets_impl.h

@@ -84,6 +84,9 @@ class LwIPSocketImpl {
 
   int get_fd() const { return this->fd_; }
 
+  /// UDP rx drop counter parity with LWIPRawUDPImpl; drops are not counted here.
+  uint16_t get_rx_dropped() const { return 0; }
+
  protected:
   // fd_ < 0 means "not open" — used both pre-open (initial state) and post-close. This
   // replaces a separate closed_ flag: close() sets fd_ = -1 after lwip_close(), and the

esphome/components/socket/socket.cpp

@@ -116,25 +116,7 @@ size_t format_sockaddr_to(const struct sockaddr *addr_ptr, socklen_t len, std::s
   return 0;
 }
 
-std::unique_ptr<Socket> socket_ip(int type, int protocol) {
-#if USE_NETWORK_IPV6
-  return socket(AF_INET6, type, protocol);
-#else
-  return socket(AF_INET, type, protocol);
-#endif /* USE_NETWORK_IPV6 */
-}
-
-#ifdef USE_SOCKET_IMPL_LWIP_TCP
-// LWIP_TCP has separate Socket/ListenSocket types — needs out-of-line factory.
-// BSD and LWIP_SOCKETS define this inline in socket.h.
-std::unique_ptr<ListenSocket> socket_ip_loop_monitored(int type, int protocol) {
-#if USE_NETWORK_IPV6
-  return socket_listen_loop_monitored(AF_INET6, type, protocol);
-#else
-  return socket_listen_loop_monitored(AF_INET, type, protocol);
-#endif /* USE_NETWORK_IPV6 */
-}
-#endif
+std::unique_ptr<Socket> socket_ip(int type, int protocol) { return socket(IP_DOMAIN, type, protocol); }
 
 socklen_t set_sockaddr(struct sockaddr *addr, socklen_t addrlen, const char *ip_address, uint16_t port) {
 #if USE_NETWORK_IPV6

esphome/components/socket/socket.h

@@ -20,6 +20,7 @@
 #include "lwip_sockets_impl.h"
 #elif defined(USE_SOCKET_IMPL_LWIP_TCP)
 #include "lwip_raw_tcp_impl.h"
+#include "lwip_raw_udp_impl.h"
 #endif
 
 namespace esphome::socket {
@@ -27,17 +28,32 @@ namespace esphome::socket {
 // Type aliases — only one implementation is active per build.
 // Socket is the concrete type for connected sockets.
 // ListenSocket is the concrete type for listening/server sockets.
-// On BSD and LWIP_SOCKETS, both aliases resolve to the same type.
+// UDPSocket is the concrete type for UDP sockets (send + receive).
+// UDPSendSocket is the concrete type for send-only UDP sockets.
+// On BSD and LWIP_SOCKETS, all aliases resolve to the same type.
 // On LWIP_TCP, they are different types (no virtual dispatch between them).
 #ifdef USE_SOCKET_IMPL_BSD_SOCKETS
 using Socket = BSDSocketImpl;
 using ListenSocket = BSDSocketImpl;
+using UDPSendSocket = BSDSocketImpl;
+using UDPSocket = BSDSocketImpl;
 #elif defined(USE_SOCKET_IMPL_LWIP_SOCKETS)
 using Socket = LwIPSocketImpl;
 using ListenSocket = LwIPSocketImpl;
+using UDPSendSocket = LwIPSocketImpl;
+using UDPSocket = LwIPSocketImpl;
 #elif defined(USE_SOCKET_IMPL_LWIP_TCP)
 using Socket = LWIPRawImpl;
 using ListenSocket = LWIPRawListenImpl;
+using UDPSendSocket = LWIPRawUDPSendImpl;
+using UDPSocket = LWIPRawUDPImpl;
+#endif
+
+// Domain used by the socket_ip_* helpers: newest available IP domain.
+#if USE_NETWORK_IPV6
+inline constexpr int IP_DOMAIN = AF_INET6;
+#else
+inline constexpr int IP_DOMAIN = AF_INET;
 #endif
 
 #ifdef USE_LWIP_FAST_SELECT
@@ -104,6 +120,36 @@ std::unique_ptr<Socket> socket_ip(int type, int protocol);
 /// File descriptors >= FD_SETSIZE will not be monitored and will log an error.
 std::unique_ptr<Socket> socket_loop_monitored(int domain, int type, int protocol);
 
+/// Create a send-only UDP socket (socket_udp_send), a UDP socket with receive
+/// support (socket_udp), or a UDP socket monitored for data in the main loop
+/// (socket_udp_loop_monitored).
+#ifdef USE_SOCKET_IMPL_LWIP_TCP
+std::unique_ptr<UDPSendSocket> socket_udp_send(int domain, int protocol);
+std::unique_ptr<UDPSocket> socket_udp(int domain, int protocol);
+// Wake is built into the recv callback, so monitoring needs nothing extra.
+inline std::unique_ptr<UDPSocket> socket_udp_loop_monitored(int domain, int protocol) {
+  return socket_udp(domain, protocol);
+}
+#else
+inline std::unique_ptr<UDPSendSocket> socket_udp_send(int domain, int protocol) {
+  return esphome::socket::socket(domain, SOCK_DGRAM, protocol);
+}
+inline std::unique_ptr<UDPSocket> socket_udp(int domain, int protocol) {
+  return esphome::socket::socket(domain, SOCK_DGRAM, protocol);
+}
+// Registers the socket with the Application's select() loop.
+inline std::unique_ptr<UDPSocket> socket_udp_loop_monitored(int domain, int protocol) {
+  return socket_loop_monitored(domain, SOCK_DGRAM, protocol);
+}
+#endif
+
+/// socket_udp* variants using the newest available IP domain.
+inline std::unique_ptr<UDPSendSocket> socket_ip_udp_send(int protocol) { return socket_udp_send(IP_DOMAIN, protocol); }
+inline std::unique_ptr<UDPSocket> socket_ip_udp(int protocol) { return socket_udp(IP_DOMAIN, protocol); }
+inline std::unique_ptr<UDPSocket> socket_ip_udp_loop_monitored(int protocol) {
+  return socket_udp_loop_monitored(IP_DOMAIN, protocol);
+}
+
 /// Create a listening socket of the given domain, type and protocol.
 /// Create a listening socket and monitor it for data in the main loop.
 /// Create a listening socket in the newest available IP domain and monitor it.
@@ -111,7 +157,6 @@ std::unique_ptr<Socket> socket_loop_monitored(int domain, int type, int protocol
 // LWIP_TCP has separate Socket/ListenSocket types — needs distinct factory functions.
 std::unique_ptr<ListenSocket> socket_listen(int domain, int type, int protocol);
 std::unique_ptr<ListenSocket> socket_listen_loop_monitored(int domain, int type, int protocol);
-std::unique_ptr<ListenSocket> socket_ip_loop_monitored(int type, int protocol);
 #else
 // BSD and LWIP_SOCKETS: Socket == ListenSocket, so listen variants just delegate.
 inline std::unique_ptr<ListenSocket> socket_listen(int domain, int type, int protocol) {
@@ -120,14 +165,10 @@ inline std::unique_ptr<ListenSocket> socket_listen(int domain, int type, int pro
 inline std::unique_ptr<ListenSocket> socket_listen_loop_monitored(int domain, int type, int protocol) {
   return socket_loop_monitored(domain, type, protocol);
 }
+#endif
 inline std::unique_ptr<ListenSocket> socket_ip_loop_monitored(int type, int protocol) {
-#if USE_NETWORK_IPV6
-  return socket_loop_monitored(AF_INET6, type, protocol);
-#else
-  return socket_loop_monitored(AF_INET, type, protocol);
-#endif
+  return socket_listen_loop_monitored(IP_DOMAIN, type, protocol);
 }
-#endif
 
 /// Set a sockaddr to the specified address and port for the IP version used by socket_ip().
 /// @param addr Destination sockaddr structure

esphome/components/speaker/media_player/audio_pipeline.cpp

@@ -202,15 +202,8 @@ AudioPipelineState AudioPipeline::process_state() {
     if (!this->is_playing_) {
       // The tasks have been stopped for two ``process_state`` calls in a row, so delete the tasks
       if (this->read_task_.is_created() || this->decode_task_.is_created()) {
-        // Both are attempted every time; a task that is still running on the other core is freed by a
-        // subsequent call, and freeing an already freed task succeeds without doing anything
-        bool read_task_freed = this->read_task_.deallocate();
-        bool decode_task_freed = this->decode_task_.deallocate();
-        if (!read_task_freed || !decode_task_freed) {
-          // A task is still running on the other core, so keep the pipeline in its current state and try
-          // again on the next call
-          return AudioPipelineState::PLAYING;
-        }
+        this->read_task_.deallocate();
+        this->decode_task_.deallocate();
         if (this->hard_stop_) {
           // Stop command was sent, so immediately end the playback
           this->speaker_->stop();
@@ -322,17 +315,17 @@ void AudioPipeline::read_task(void *params) {
       if (err == ESP_OK) {
         size_t file_ring_buffer_size = this_pipeline->buffer_size_;
 
-        std::shared_ptr<ring_buffer::RingBuffer> temp_ring_buffer = this_pipeline->raw_file_ring_buffer_.lock();
+        std::shared_ptr<ring_buffer::RingBuffer> temp_ring_buffer;
 
-        if (temp_ring_buffer == nullptr) {
+        if (!this_pipeline->raw_file_ring_buffer_.use_count()) {
           temp_ring_buffer = ring_buffer::RingBuffer::create(file_ring_buffer_size);
           this_pipeline->raw_file_ring_buffer_ = temp_ring_buffer;
         }
 
-        if (temp_ring_buffer == nullptr) {
+        if (!this_pipeline->raw_file_ring_buffer_.use_count()) {
           err = ESP_ERR_NO_MEM;
         } else {
-          err = reader->add_sink(temp_ring_buffer);
+          reader->add_sink(this_pipeline->raw_file_ring_buffer_);
         }
       }
 
@@ -403,9 +396,7 @@ void AudioPipeline::decode_task(void *params) {
           make_unique<audio::AudioDecoder>(this_pipeline->transfer_buffer_size_, this_pipeline->transfer_buffer_size_);
 
       esp_err_t err = decoder->start(this_pipeline->current_audio_file_type_);
-      if (err == ESP_OK) {
-        err = decoder->add_source(this_pipeline->raw_file_ring_buffer_);
-      }
+      decoder->add_source(this_pipeline->raw_file_ring_buffer_);
 
       if (err != ESP_OK) {
         // Send specific error message

esphome/components/wifi/__init__.py

@@ -66,13 +66,14 @@ from esphome.const import (
 )
 from esphome.core import (
     CORE,
+    ID,
     CoroPriority,
     EsphomeError,
     HexInt,
     coroutine_with_priority,
 )
 import esphome.final_validate as fv
-from esphome.types import ConfigType
+from esphome.types import ConfigType, TemplateArgsType
 
 from . import wpa2_eap
 
@@ -208,6 +209,7 @@ WiFiEnabledCondition = wifi_ns.class_("WiFiEnabledCondition", Condition)
 WiFiAPActiveCondition = wifi_ns.class_("WiFiAPActiveCondition", Condition)
 WiFiEnableAction = wifi_ns.class_("WiFiEnableAction", automation.Action)
 WiFiDisableAction = wifi_ns.class_("WiFiDisableAction", automation.Action)
+WiFiRoamAction = wifi_ns.class_("WiFiRoamAction", automation.Action)
 WiFiConfigureAction = wifi_ns.class_(
     "WiFiConfigureAction", automation.Action, cg.Component
 )
@@ -820,6 +822,18 @@ async def wifi_disable_to_code(config, action_id, template_arg, args):
     return cg.new_Pvariable(action_id, template_arg)
 
 
+@automation.register_action(
+    "wifi.roam", WiFiRoamAction, cv.Schema({}), synchronous=True
+)
+async def wifi_roam_to_code(
+    config: ConfigType,
+    action_id: ID,
+    template_arg: cg.TemplateArguments,
+    args: TemplateArgsType,
+) -> cg.MockObj:
+    return cg.new_Pvariable(action_id, template_arg)
+
+
 KEEP_SCAN_RESULTS_KEY = "wifi_keep_scan_results"
 RUNTIME_POWER_SAVE_KEY = "wifi_runtime_power_save"
 RUNTIME_ROAMING_SUPPRESSION_KEY = "wifi_runtime_roaming_suppression"

esphome/components/wifi/automation.h

@@ -31,6 +31,11 @@ template<typename... Ts> class WiFiDisableAction final : public Action<Ts...> {
   void play(const Ts &...x) override { global_wifi_component->disable(); }
 };
 
+template<typename... Ts> class WiFiRoamAction final : public Action<Ts...> {
+ public:
+  void play(const Ts &...x) override { global_wifi_component->force_roam_check(); }
+};
+
 template<typename... Ts> class WiFiConfigureAction final : public Action<Ts...>, public Component {
  public:
   TEMPLATABLE_VALUE(std::string, ssid)

esphome/components/wifi/wifi_component.cpp

@@ -846,17 +846,18 @@ void WiFiComponent::loop() {
           this->notify_connect_state_listeners_();
 #endif
 
-          // Post-connect roaming: check for better AP
-          if (this->post_connect_roaming_) {
-            if (this->is_roaming_scan_active()) {
-              if (this->scan_done_) {
-                this->process_roaming_scan_();
-              }
-              // else: scan in progress, wait
-            } else if (this->roaming_state_ == RoamingState::IDLE && this->roaming_attempts_ < ROAMING_MAX_ATTEMPTS &&
-                       now - this->roaming_last_check_ >= ROAMING_CHECK_INTERVAL && !this->roaming_suppressed_()) {
-              this->check_roaming_(now);
+          // Post-connect roaming: check for better AP. A scan may have been started by an
+          // explicit force_roam_check() even when post_connect_roaming_ is disabled, so the
+          // scan must always be consumed here to avoid leaving roaming_state_ stuck.
+          if (this->is_roaming_scan_active()) {
+            if (this->scan_done_) {
+              this->process_roaming_scan_();
             }
+            // else: scan in progress, wait
+          } else if (this->post_connect_roaming_ && this->roaming_state_ == RoamingState::IDLE &&
+                     this->roaming_attempts_ < ROAMING_MAX_ATTEMPTS &&
+                     now - this->roaming_last_check_ >= ROAMING_CHECK_INTERVAL && !this->roaming_suppressed_()) {
+            this->check_roaming_(now);
           }
         }
         break;
@@ -2463,6 +2464,17 @@ void WiFiComponent::notify_scan_results_listeners_() {
 }
 #endif  // USE_WIFI_SCAN_RESULTS_LISTENERS
 
+void WiFiComponent::force_roam_check() {
+  if (!this->is_connected() || this->roaming_state_ != RoamingState::IDLE || this->roaming_suppressed_()) {
+    ESP_LOGD(TAG, "Roam check requested, but not able to check now");
+    return;
+  }
+  // Reset the attempt counter so a prior run of failed roams doesn't block this explicit request
+  // Note that this re-arms automatic roaming if enabled.
+  this->roaming_attempts_ = 0;
+  this->check_roaming_(millis());
+}
+
 void WiFiComponent::check_roaming_(uint32_t now) {
   // Guard: not for hidden networks (may not appear in scan)
   const WiFiAP *selected = this->get_selected_sta_();
@@ -2484,7 +2496,11 @@ void WiFiComponent::check_roaming_(uint32_t now) {
 
   ESP_LOGD(TAG, "Roam scan (%d dBm, attempt %u/%u)", rssi, this->roaming_attempts_, ROAMING_MAX_ATTEMPTS);
   this->roaming_state_ = RoamingState::SCANNING;
-  this->wifi_scan_start_(this->passive_scan_);
+  if (!this->wifi_scan_start_(this->passive_scan_)) {
+    // Scan failed to start (e.g. busy) - don't get stuck in SCANNING forever
+    ESP_LOGD(TAG, "Roam scan failed to start");
+    this->roaming_state_ = RoamingState::IDLE;
+  }
 }
 
 void WiFiComponent::process_roaming_scan_() {

esphome/components/wifi/wifi_component.h

@@ -565,6 +565,12 @@ class WiFiComponent final : public Component {
   void set_keep_scan_results(bool keep_scan_results) { this->keep_scan_results_ = keep_scan_results; }
   void set_post_connect_roaming(bool enabled) { this->post_connect_roaming_ = enabled; }
 
+  /** Force an immediate post-connect roaming check, bypassing the periodic interval and the
+   * per-connection attempt limit. Does nothing (besides a debug log) if not connected, if a
+   * roam scan or connect is already in progress, or if roaming is currently suppressed.
+   */
+  void force_roam_check();
+
 #ifdef USE_WIFI_CONNECT_TRIGGER
   Trigger<> *get_connect_trigger() { return &this->connect_trigger_; }
 #endif

esphome/const.py

@@ -4,7 +4,7 @@ from enum import Enum
 
 from esphome.enum import StrEnum
 
-__version__ = "2026.9.0b3"
+__version__ = "2026.10.0-dev"
 
 ALLOWED_NAME_CHARS = "abcdefghijklmnopqrstuvwxyz0123456789-_"
 VALID_SUBSTITUTIONS_CHARACTERS = (

esphome/core/static_task.cpp

@@ -40,31 +40,16 @@ bool StaticTask::create(TaskFunction_t fn, const char *name, uint32_t stack_size
   return true;
 }
 
-bool StaticTask::destroy() {
-  if (this->handle_ == nullptr) {
-    return true;
+void StaticTask::destroy() {
+  if (this->handle_ != nullptr) {
+    TaskHandle_t handle = this->handle_;
+    this->handle_ = nullptr;
+    vTaskDelete(handle);
   }
-
-  // Suspending takes the task off the ready and event lists, so nothing can schedule it again. It only asks
-  // the other core to yield though, so the task may still be running on it for a moment.
-  vTaskSuspend(this->handle_);
-  if (eTaskGetState(this->handle_) != eSuspended) {
-    // The task is still running on the other core and using its stack. Deleting it now would only put it on
-    // the termination list and return, so the caller has to try again once it has been swapped out.
-    return false;
-  }
-
-  // The task cannot run again, so the delete completes right away instead of being left to the idle task.
-  TaskHandle_t handle = this->handle_;
-  this->handle_ = nullptr;
-  vTaskDelete(handle);
-  return true;
 }
 
-bool StaticTask::deallocate() {
-  if (!this->destroy()) {
-    return false;
-  }
+void StaticTask::deallocate() {
+  this->destroy();
   if (this->stack_buffer_ != nullptr) {
     RAMAllocator<StackType_t> allocator(this->use_psram_ ? RAMAllocator<StackType_t>::ALLOC_EXTERNAL
                                                          : RAMAllocator<StackType_t>::ALLOC_INTERNAL);
@@ -72,7 +57,6 @@ bool StaticTask::deallocate() {
     this->stack_buffer_ = nullptr;
     this->stack_size_ = 0;
   }
-  return true;
 }
 
 }  // namespace esphome

esphome/core/static_task.h

@@ -11,7 +11,6 @@ namespace esphome {
 
 /** Helper for FreeRTOS static task management.
  * Bundles TaskHandle_t, StaticTask_t, and the stack buffer into one object with create/destroy methods.
- * Call destroy() and deallocate() from another task: a task cannot free the stack it is still running on.
  */
 class StaticTask {
  public:
@@ -24,7 +23,7 @@ class StaticTask {
   /// @brief Allocate stack and create task.
   /// @param fn         Task function
   /// @param name       Task name (for debug)
-  /// @param stack_size Stack size in bytes (StackType_t is a byte on ESP-IDF)
+  /// @param stack_size Stack size in StackType_t words
   /// @param param      Parameter passed to task function
   /// @param priority   FreeRTOS task priority
   /// @param use_psram  If true, allocate stack in PSRAM; otherwise internal RAM
@@ -32,17 +31,11 @@ class StaticTask {
   bool create(TaskFunction_t fn, const char *name, uint32_t stack_size, void *param, UBaseType_t priority,
               bool use_psram);
 
-  /// @brief Delete the task, keeping the stack buffer allocated for reuse by a subsequent create() call.
-  /// The task must have finished its work and parked itself, either suspended or blocked indefinitely: it is
-  /// suspended here so that it cannot be scheduled again, and it is given no chance to clean up.
-  /// @return true if the task was deleted; false if it is still running on another core, in which case the
-  /// caller should try again later.
-  bool destroy();
+  /// @brief Delete the task but keep the stack buffer allocated for reuse by a subsequent create() call.
+  void destroy();
 
-  /// @brief Delete the task (if created) and free the stack buffer.
-  /// @return true if the stack buffer was freed; false if the task is still running on another core, in
-  /// which case the caller should try again later.
-  bool deallocate();
+  /// @brief Delete the task (if running) and free the stack buffer.
+  void deallocate();
 
  protected:
   TaskHandle_t handle_{nullptr};

esphome/espota2.py

@@ -96,10 +96,6 @@ UPLOAD_BUFFER_SIZE = UPLOAD_BLOCK_SIZE * 8
 # across the addresses on top of that.
 EXTRA_UPLOAD_ATTEMPTS = 2
 UPLOAD_RETRY_DELAY = 5.0
-# Data phase timeout; must stay longer than the device's OTA_SOCKET_TIMEOUT_DATA
-# (105 s) so a stalled session is gone before a retry, and long enough for lwIP
-# to get a lost chunk ack through after the retransmit run seen in practice
-DATA_PHASE_TIMEOUT = 160.0
 
 _LOGGER = logging.getLogger(__name__)
 
@@ -698,7 +694,8 @@ def perform_ota(
 
     _LOGGER.info("Handshake complete")
 
-    sock.settimeout(DATA_PHASE_TIMEOUT)
+    # Timeout must match device-side OTA_SOCKET_TIMEOUT_DATA to prevent premature failures
+    sock.settimeout(90.0)
 
     if extended_proto:
         send_check(sock, ota_type, "ota type")
@@ -857,7 +854,7 @@ def run_ota_impl_(
     # clean up a half-open connection (its handshake watchdog runs at 20s);
     # moving on to the next address family stays immediate. Known limitation:
     # a silent mid-transfer drop with no reset can wedge the device until its
-    # 105s data timeout, which outlasts this budget; the retries target the
+    # 90s data timeout, which outlasts this budget; the retries target the
     # common failures where the device resets or closes the link promptly.
     total_attempts = len(res) + EXTRA_UPLOAD_ATTEMPTS
     last_error = ""

esphome/happy_eyeballs.py

@@ -69,10 +69,7 @@ def _make_create_connection() -> Callable[..., socket.socket]:
 
     from aiohappyeyeballs import start_connection
     from urllib3.exceptions import LocationParseError
-    from urllib3.util.connection import (  # noqa: PLC2701
-        _set_socket_options,
-        allowed_gai_family,
-    )
+    from urllib3.util.connection import _set_socket_options, allowed_gai_family  # noqa: PLC2701
     from urllib3.util.timeout import _DEFAULT_TIMEOUT  # noqa: PLC2701
 
     from esphome import async_thread

platformio.ini

@@ -45,7 +45,7 @@ lib_deps_base =
 lib_deps =
     ${common.lib_deps_base}
     https://github.com/dudanov/MideaUART.git#eeea6c3e9b4474f067054592b435be1c4e466815 ; midea
-    esphome/noise-c@0.1.26                 ; noise (api, ota)
+    esphome/noise-c@0.1.24                 ; noise (api, ota)
     improv/Improv@1.2.7                    ; improv_serial / esp32_improv
     kikuchan98/pngle@1.1.0                 ; online_image
     ; Using the repository directly, otherwise ESP-IDF can't use the library
@@ -244,7 +244,7 @@ lib_deps =
     ${common:idf-component-libs.lib_deps}
     ESP32Async/ESPAsyncWebServer@3.9.6    ; web_server_base
     droscy/esp_wireguard@0.4.5            ; wireguard
-    esphome/noise-c@0.1.26                ; noise (api, ota)
+    esphome/noise-c@0.1.24                ; noise (api, ota)
     ESP32Async/AsyncTCP@3.4.5             ; async_tcp
     DNSServer                             ; captive_portal
     heman/AsyncMqttClient-esphome@2.0.0   ; mqtt
@@ -641,7 +641,7 @@ build_unflags =
 extends = common
 platform = platformio/native
 lib_deps =
-    esphome/noise-c@0.1.26  ; used by noise (api, ota)
+    esphome/noise-c@0.1.24  ; used by noise (api, ota)
     lvgl/lvgl@9.5.0         ; lvgl
 build_flags =
     ${common.build_flags}

requirements.txt

@@ -14,7 +14,7 @@ esptool==5.3.1
 click==8.3.3
 aioesphomeapi==46.3.0
 aiohappyeyeballs==2.7.1  # Happy Eyeballs for requests downloads; already pulled in by aioesphomeapi
-zeroconf==0.151.2
+zeroconf==0.151.3
 puremagic==2.2.0
 ruamel.yaml==0.19.1 # dashboard_import
 ruamel.yaml.clib==0.2.15 # dashboard_import
@@ -27,9 +27,9 @@ bleak==3.0.2
 smpclient==7.2.0
 requests==2.34.2
 py7zr==1.1.3
-platformdirs==4.11.5  # native esp-idf toolchain global cache dir
-ninja==1.13.0  # native esp8266 arduino toolchain build driver
-filelock==3.32.4  # inter-process locks (PlatformIO cache heal, git clone cache); >=3.32 for FileLock(fallback_to_soft=...), older versions silently drop the kwarg
+platformdirs==4.11.7  # native esp-idf toolchain global cache dir
+ninja==1.13.2  # native esp8266 arduino toolchain build driver
+filelock==3.32.5  # inter-process locks (PlatformIO cache heal, git clone cache); >=3.32 for FileLock(fallback_to_soft=...), older versions silently drop the kwarg
 
 # esp-idf >= 5.0 requires this
 pyparsing >= 3.3.2

requirements_dev.txt

@@ -1,4 +1,4 @@
 # Useful stuff when working in a development environment
-clang-format==13.0.1  # also change in .pre-commit-config.yaml and Dockerfile when updating
+clang-format==13.0.1  # .pre-commit-config.yaml rev synced by script/sync_dependency_versions.py
 clang-tidy==22.1.8
-yamllint==1.38.0  # also change in .pre-commit-config.yaml when updating
+yamllint==1.38.0  # .pre-commit-config.yaml rev synced by script/sync_dependency_versions.py

requirements_test.txt

@@ -1,8 +1,9 @@
 pylint==4.0.8
-flake8==7.3.0  # also change in .pre-commit-config.yaml when updating
-ruff==0.16.5  # also change in .pre-commit-config.yaml when updating
-pyupgrade==3.21.2  # also change in .pre-commit-config.yaml when updating
-prek==0.5.0  # also change in .github/workflows/ci.yml when updating
+flake8==7.3.0  # .pre-commit-config.yaml rev synced by script/sync_dependency_versions.py
+ruff==0.16.6  # .pre-commit-config.yaml rev synced by script/sync_dependency_versions.py
+pyupgrade==3.21.2  # .pre-commit-config.yaml rev synced by script/sync_dependency_versions.py
+prek==0.5.2  # .github/workflows/ci.yml reads this pin
+yamlrocks==0.6.1  # used by script/sync_dependency_versions.py
 
 # Unit tests
 pytest==9.1.1

script/git-hooks/post-checkout

@@ -14,7 +14,31 @@ top=$(git rev-parse --show-toplevel 2>/dev/null) || exit 0
 [ -x "$top/venv/bin/python" ] && exit 0
 [ -x "$top/script/setup" ] || exit 0
 
+# Every worktree shares the hooks directory of the checkout it was created
+# from, and the script/setup run below is the one from whichever branch was just
+# checked out. Older branches install their own pre-commit hook without checking
+# for a worktree: that moves the shared hook aside as pre-commit.legacy and
+# replaces it with one tied to this worktree's virtual environment, so commits
+# break in every checkout. To rule that out, the hooks directory is copied
+# before script/setup runs and put back exactly as it was afterwards, including
+# removing any file script/setup added.
+hooks=$(git rev-parse --path-format=absolute --git-path hooks 2>/dev/null) || exit 0
+snap=$(mktemp -d "$hooks/.post-checkout.XXXXXX") || exit 0
+cp -p "$hooks"/* "$snap"/ 2>/dev/null
+
 # Clear VIRTUAL_ENV so a checkout made from a shell with an environment already
 # activated still gets its own, rather than having the active one repointed at
 # this working tree.
-exec env -u VIRTUAL_ENV "$top/script/setup"
+env -u VIRTUAL_ENV "$top/script/setup"
+status=$?
+
+for f in "$hooks"/*; do
+  [ -e "$snap/${f##*/}" ] || rm -f "$f"
+done
+# Files are moved rather than copied so a hook that is still running, such as
+# this one, is swapped out atomically instead of being rewritten in place.
+for f in "$snap"/*; do
+  cmp -s "$f" "$hooks/${f##*/}" 2>/dev/null || mv -f "$f" "$hooks/${f##*/}"
+done
+rm -rf "$snap"
+exit $status

script/helpers.py

@@ -1104,6 +1104,10 @@ def get_components_per_integration_fixture() -> dict[str, set[str]]:
 
 
 _TEST_FUNC_RE = re.compile(r"async def (test_\w+)")
+# Any usage form (decorator, pytestmark assignment or list element); only
+# test_*.py files are scanned, so the marker docs elsewhere cannot false-hit
+_SHARED_YAML_USE_RE = re.compile(r"\bmark\.shared_yaml")
+_SHARED_YAML_ARG_RE = re.compile(r"\(\s*[\"'](\w+)[\"']\s*\)")
 
 
 @cache
@@ -1123,6 +1127,19 @@ def get_fixture_to_test_files() -> dict[str, frozenset[str]]:
         for func in _TEST_FUNC_RE.findall(content):
             base_name = func.replace("test_", "").partition("[")[0]
             result.setdefault(base_name, set()).add(rel_path)
+        # Shared fixtures are named by marker, not by a test function; each
+        # decorator must carry a string literal or its fixture would silently
+        # map to no tests
+        for use in _SHARED_YAML_USE_RE.finditer(content):
+            arg = _SHARED_YAML_ARG_RE.match(content, use.end())
+            if arg is None:
+                line = content.count("\n", 0, use.start()) + 1
+                raise ValueError(
+                    f"{rel_path}:{line}: shared_yaml marker must take a "
+                    "single-line string literal so CI test selection can map "
+                    "its fixture"
+                )
+            result.setdefault(arg.group(1), set()).add(rel_path)
 
     return {k: frozenset(v) for k, v in result.items()}
 

script/sync_dependency_versions.py

@@ -0,0 +1,164 @@
+#!/usr/bin/env python3
+"""Keep pre-commit hook revs in sync with the requirements files.
+
+Dependabot only bumps the ``package==version`` pins in ``requirements*.txt``.
+Some of those tools are pinned a second time as hook ``rev`` values in
+``.pre-commit-config.yaml``. This script treats the requirements files as
+the source of truth and rewrites the revs to match, editing the config
+through yamlrocks so comments and layout survive.
+
+Run without arguments to apply the changes in place, or with ``--check`` to
+only report drift (exit status 1 when anything is out of sync).
+"""
+
+from __future__ import annotations
+
+import argparse
+from dataclasses import dataclass
+from pathlib import Path
+import re
+import sys
+from typing import Any
+
+import yamlrocks
+
+REPO_ROOT = Path(__file__).resolve().parent.parent
+PRECOMMIT_CONFIG = ".pre-commit-config.yaml"
+
+
+class SyncError(Exception):
+    """A pin could not be located in a requirements file or the config."""
+
+
+@dataclass(frozen=True)
+class SyncTarget:
+    """A requirements pin and the pre-commit repo whose rev mirrors it."""
+
+    package: str
+    requirements_file: str
+    repo: str
+
+
+SYNC_TARGETS: tuple[SyncTarget, ...] = (
+    SyncTarget(
+        "ruff", "requirements_test.txt", "https://github.com/astral-sh/ruff-pre-commit"
+    ),
+    SyncTarget("flake8", "requirements_test.txt", "https://github.com/PyCQA/flake8"),
+    SyncTarget(
+        "pyupgrade", "requirements_test.txt", "https://github.com/asottile/pyupgrade"
+    ),
+    SyncTarget(
+        "clang-format",
+        "requirements_dev.txt",
+        "https://github.com/pre-commit/mirrors-clang-format",
+    ),
+    SyncTarget(
+        "yamllint",
+        "requirements_dev.txt",
+        "https://github.com/adrienverge/yamllint.git",
+    ),
+)
+
+
+def read_requirement_version(requirements: str, package: str) -> str | None:
+    """Return the ``==`` pin for ``package`` or None when it is not pinned."""
+    pattern = re.compile(
+        rf"^{re.escape(package)}==(?P<version>[^\s#]+)",
+        re.MULTILINE | re.IGNORECASE,
+    )
+    match = pattern.search(requirements)
+    return match.group("version") if match else None
+
+
+def find_repo_entry(doc: Any, repo: str) -> Any:
+    """Return the single ``- repo:`` block for ``repo`` in a pre-commit doc."""
+    try:
+        entries = [entry for entry in doc["repos"] if entry["repo"] == repo]
+    except KeyError as err:
+        raise SyncError(f"malformed pre-commit config, missing key {err}") from None
+    if len(entries) != 1:
+        raise SyncError(
+            f"expected exactly one block for repo {repo}, found {len(entries)}"
+        )
+    return entries[0]
+
+
+def current_rev(entry: Any, repo: str) -> tuple[str, str]:
+    """Split the block's rev into its tag prefix (``v`` or empty) and version."""
+    if "rev" not in entry:
+        raise SyncError(f"repo {repo} has no rev")
+    rev = entry["rev"]
+    if not isinstance(rev, str):
+        # A rev such as ``1.0`` parses as a number and cannot be compared or
+        # rewritten safely; quote it in the config instead.
+        raise SyncError(f"rev of repo {repo} is not a string: {rev!r}")
+    prefix = "v" if rev.startswith("v") else ""
+    return prefix, rev.removeprefix("v")
+
+
+def sync(root: Path, *, write: bool) -> list[str]:
+    """Bring every hook rev in line with its requirements pin.
+
+    Returns one description per rev that was (or, when ``write`` is False,
+    would be) changed. Raises SyncError when a pin cannot be found, which
+    means SYNC_TARGETS has gone stale and needs updating by hand.
+    """
+    config_path = root / PRECOMMIT_CONFIG
+    doc = yamlrocks.loads(config_path.read_bytes(), option=yamlrocks.OPT_ROUND_TRIP)
+    requirements: dict[str, str] = {}
+    changes: list[str] = []
+    for target in SYNC_TARGETS:
+        if target.requirements_file not in requirements:
+            requirements[target.requirements_file] = (
+                root / target.requirements_file
+            ).read_text()
+        version = read_requirement_version(
+            requirements[target.requirements_file], target.package
+        )
+        if version is None:
+            raise SyncError(
+                f"{target.requirements_file}: no '{target.package}==' pin found"
+            )
+
+        entry = find_repo_entry(doc, target.repo)
+        prefix, current = current_rev(entry, target.repo)
+        if current == version:
+            continue
+        changes.append(f"{target.package}: {current} -> {version}")
+        entry["rev"] = f"{prefix}{version}"
+
+    if changes and write:
+        config_path.write_bytes(doc.to_yaml())
+    return changes
+
+
+def main(argv: list[str] | None = None) -> int:
+    parser = argparse.ArgumentParser(description=__doc__.splitlines()[0])
+    parser.add_argument(
+        "--check",
+        action="store_true",
+        help="report drift without modifying any file; exit 1 if out of sync",
+    )
+    parser.add_argument(
+        "--root",
+        type=Path,
+        default=REPO_ROOT,
+        help="repository checkout to operate on (default: this checkout)",
+    )
+    args = parser.parse_args(argv)
+
+    try:
+        changes = sync(args.root, write=not args.check)
+    except SyncError as err:
+        print(f"error: {err}", file=sys.stderr)
+        return 1
+
+    for change in changes:
+        print(change)
+    if args.check and changes:
+        return 1
+    return 0
+
+
+if __name__ == "__main__":  # pragma: no cover
+    sys.exit(main())

tests/component_tests/sendspin/test_media_source.py

@@ -1,90 +0,0 @@
-"""Validation tests for the sendspin media_source platform.
-
-These cover the codec preference list, whose rejection branches a compile test
-cannot reach: a `test*.yaml` can only assert that a configuration is accepted.
-"""
-
-from typing import Any
-
-import pytest
-
-from esphome import config_validation as cv
-from esphome.components.sendspin import CONF_CODECS, _get_data
-from esphome.components.sendspin.media_source import CONFIG_SCHEMA
-from esphome.const import PlatformFramework
-from esphome.types import ConfigType
-from tests.component_tests.types import SetCoreConfigCallable
-
-
-def _media_source_config(**overrides: Any) -> ConfigType:
-    """Build a minimal valid media source config, allowing field overrides."""
-    config: ConfigType = {
-        "id": "sendspin_media_source",
-        "sendspin_id": "sendspin_hub",
-    }
-    config.update(overrides)
-    return config
-
-
-def test_default_codecs_at_48_khz(set_core_config: SetCoreConfigCallable) -> None:
-    """Every codec is advertised when the sample rate suits all of them."""
-    set_core_config(PlatformFramework.ESP32_IDF)
-
-    config = CONFIG_SCHEMA(_media_source_config())
-
-    assert config[CONF_CODECS] == ["flac", "opus", "pcm"]
-
-
-def test_default_codecs_drop_opus_at_other_rates(
-    set_core_config: SetCoreConfigCallable,
-) -> None:
-    """Opus only supports 48 kHz, so it leaves the default list at other rates."""
-    set_core_config(PlatformFramework.ESP32_IDF)
-
-    config = CONFIG_SCHEMA(_media_source_config(sample_rate=44100))
-
-    assert config[CONF_CODECS] == ["flac", "pcm"]
-
-
-def test_configured_order_is_preserved(set_core_config: SetCoreConfigCallable) -> None:
-    """The list is a preference order, so it reaches the player role as written."""
-    set_core_config(PlatformFramework.ESP32_IDF)
-
-    CONFIG_SCHEMA(_media_source_config(codecs=["pcm", "flac"]))
-
-    assert _get_data().player_config[CONF_CODECS] == ["pcm", "flac"]
-
-
-def test_empty_codec_list_rejected(set_core_config: SetCoreConfigCallable) -> None:
-    """A player with no codecs at all could never be given a stream."""
-    set_core_config(PlatformFramework.ESP32_IDF)
-
-    with pytest.raises(cv.Invalid, match="length of value must be at least 1"):
-        CONFIG_SCHEMA(_media_source_config(codecs=[]))
-
-
-def test_duplicate_codec_rejected(set_core_config: SetCoreConfigCallable) -> None:
-    """A repeated codec has no meaning in a preference order."""
-    set_core_config(PlatformFramework.ESP32_IDF)
-
-    with pytest.raises(cv.Invalid, match="may only be listed once"):
-        CONFIG_SCHEMA(_media_source_config(codecs=["flac", "flac"]))
-
-
-def test_unknown_codec_rejected(set_core_config: SetCoreConfigCallable) -> None:
-    """Only codecs the player role can decode are accepted."""
-    set_core_config(PlatformFramework.ESP32_IDF)
-
-    with pytest.raises(cv.Invalid, match="Unknown value"):
-        CONFIG_SCHEMA(_media_source_config(codecs=["mp3"]))
-
-
-def test_opus_at_wrong_sample_rate_rejected(
-    set_core_config: SetCoreConfigCallable,
-) -> None:
-    """Asking for Opus at a rate it cannot handle fails rather than silently
-    dropping the stated preference."""
-    set_core_config(PlatformFramework.ESP32_IDF)
-
-    with pytest.raises(cv.Invalid, match="requires a sample_rate of 48000"):
-        CONFIG_SCHEMA(_media_source_config(codecs=["opus"], sample_rate=44100))

tests/components/sendspin/common-media_source.yaml

@@ -9,4 +9,3 @@ media_source:
     static_delay_adjustable: true
     fixed_delay: 480us
     decode_memory: internal
-    codecs: [pcm, opus, flac]

tests/components/wifi/common.yaml

@@ -14,6 +14,7 @@ esphome:
           condition: wifi.ap_active
           then:
             - logger.log: "WiFi AP is active!"
+      - wifi.roam
 
 wifi:
   networks:

tests/integration/README.md

@@ -21,6 +21,13 @@ The `yaml_config` fixture automatically loads YAML configurations based on the t
 - The fixture file must exist or the test will fail with a clear error message
 - The fixture automatically injects a dynamic port number into the API configuration
 
+Tests marked `@pytest.mark.shared_yaml("name")` load `fixtures/name.yaml` instead
+of the test-named file and compile it in a shared, hash-keyed build directory, so
+the whole group pays one full compile and each test only a relink. The marker
+argument must be a single-line string literal (CI test selection maps fixtures to
+test files by scanning for it), and marked tests must hand the `yaml_config`
+content to `run_compiled` unmodified.
+
 ### Key Fixtures
 
 - `run_compiled` - Combines write, compile, and run operations into a single context manager

tests/integration/conftest.py

@@ -4,17 +4,22 @@ from __future__ import annotations
 
 import asyncio
 from collections.abc import AsyncGenerator, Callable, Generator
-from contextlib import AbstractAsyncContextManager, asynccontextmanager
+from contextlib import AbstractAsyncContextManager, asynccontextmanager, suppress
 import fcntl
+from functools import cache
+import hashlib
 import logging
 import os
 from pathlib import Path
 import platform
+import re
+import shutil
 import signal
 import socket
 import subprocess
 import sys
 import tempfile
+import time
 from typing import TextIO
 
 from aioesphomeapi import APIClient, APIConnectionError, LogParser, ReconnectLogic
@@ -23,7 +28,13 @@ import pytest_asyncio
 
 import esphome.config
 from esphome.core import CORE
-from esphome.helpers import get_usable_cpu_count
+from esphome.helpers import (
+    get_usable_cpu_count,
+    read_file,
+    rmtree,
+    write_file,
+    write_file_if_changed,
+)
 from esphome.platformio.toolchain import get_idedata
 
 from .const import (
@@ -56,6 +67,21 @@ import pty  # not available on Windows
 pytest.register_assert_rewrite("tests.integration.entity_utils")
 
 
+def pytest_configure(config: pytest.Config) -> None:
+    config.addinivalue_line(
+        "markers",
+        "shared_yaml(name): load fixtures/<name>.yaml and compile it in a shared, "
+        "hash-keyed incremental build directory",
+    )
+
+
+FIXTURES_DIR = Path(__file__).parent / "fixtures"
+REPO_ROOT = Path(__file__).resolve().parent.parent.parent
+
+# CI caches parts of this path; keep in sync with ci.yml integration-tests.
+INTEGRATION_TESTS_ROOT = Path.home() / ".esphome-integration-tests"
+
+
 def _get_platformio_env(cache_dir: Path) -> dict[str, str]:
     """Get environment variables for PlatformIO with shared cache."""
     env = os.environ.copy()
@@ -78,7 +104,7 @@ def _get_platformio_env(cache_dir: Path) -> dict[str, str]:
         )
     # Compile with THIS tree's esphome sources, not wherever the venv's editable
     # install points (which may be a different git worktree or checkout).
-    repo_root = str(Path(__file__).resolve().parent.parent.parent)
+    repo_root = str(REPO_ROOT)
     existing = env.get("PYTHONPATH")
     env["PYTHONPATH"] = f"{repo_root}{os.pathsep}{existing}" if existing else repo_root
     return env
@@ -88,8 +114,7 @@ def _get_platformio_env(cache_dir: Path) -> dict[str, str]:
 def shared_platformio_cache() -> Generator[Path]:
     """Initialize a shared PlatformIO cache for all integration tests."""
     # Use a dedicated directory for integration tests to avoid conflicts.
-    # CI caches parts of this path; keep in sync with ci.yml integration-tests.
-    test_cache_dir = Path.home() / ".esphome-integration-tests"
+    test_cache_dir = INTEGRATION_TESTS_ROOT
     cache_dir = test_cache_dir / "platformio"
 
     # Use a lock file in the home directory to ensure only one process initializes the cache
@@ -112,7 +137,9 @@ def shared_platformio_cache() -> Generator[Path]:
                 init_dir = Path(tmpdir)
                 fixture_path = Path(__file__).parent / "fixtures" / "cache_init.yaml"
                 config_path = init_dir / "cache_init.yaml"
-                config_path.write_text(fixture_path.read_text())
+                config_path.write_text(
+                    fixture_path.read_text(encoding="utf-8"), encoding="utf-8"
+                )
 
                 # Run compilation to populate the cache
                 # We must succeed here to avoid race conditions where multiple
@@ -162,13 +189,6 @@ def integration_test_dir() -> Generator[Path]:
         yield Path(tmpdir)
 
 
-@pytest.fixture
-def isolated_preferences(monkeypatch: pytest.MonkeyPatch, tmp_path: Path) -> None:
-    """Host preferences persist per device name; give the test its own so a
-    provisioned key never leaks into another run."""
-    monkeypatch.setenv("ESPHOME_PREFDIR", str(tmp_path / "prefs"))
-
-
 @pytest.fixture
 def reserved_tcp_port() -> Generator[tuple[int, socket.socket]]:
     """Reserve an unused TCP port by holding the socket open."""
@@ -188,21 +208,29 @@ def unused_tcp_port(reserved_tcp_port: tuple[int, socket.socket]) -> int:
     return reserved_tcp_port[0]
 
 
+@pytest.fixture(autouse=True)
+def isolated_preferences(monkeypatch: pytest.MonkeyPatch, tmp_path: Path) -> Path:
+    """Give every test its own host prefs dir; prefs are keyed only by device
+    name, which tests sharing a fixture also share."""
+    prefdir = tmp_path / "prefs"
+    monkeypatch.setenv("ESPHOME_PREFDIR", str(prefdir))
+    return prefdir
+
+
 @pytest_asyncio.fixture
 async def yaml_config(request: pytest.FixtureRequest, unused_tcp_port: int) -> str:
     """Load YAML configuration based on test name."""
-    # Get the test function name
-    test_name: str = request.node.name
-    # Extract the base test name (remove test_ prefix and any parametrization)
-    base_name = test_name.replace("test_", "").partition("[")[0]
+    shared_name = _shared_yaml_name(request)
+    # Base test name: test_ prefix and any parametrization stripped
+    base_name = shared_name or request.node.name.replace("test_", "").partition("[")[0]
 
     # Load the fixture file
-    fixture_path = Path(__file__).parent / "fixtures" / f"{base_name}.yaml"
+    fixture_path = FIXTURES_DIR / f"{base_name}.yaml"
     if not fixture_path.exists():
         raise FileNotFoundError(f"Fixture file not found: {fixture_path}")
 
     loop = asyncio.get_running_loop()
-    content = await loop.run_in_executor(None, fixture_path.read_text)
+    content = await loop.run_in_executor(None, read_file, fixture_path)
 
     # Replace the port in the config if it contains api section
     if "api:" in content:
@@ -226,11 +254,13 @@ async def yaml_config(request: pytest.FixtureRequest, unused_tcp_port: int) -> s
 
     # Replace external component path placeholder if present
     if "EXTERNAL_COMPONENT_PATH" in content:
-        external_components_path = str(
-            Path(__file__).parent / "fixtures" / "external_components"
-        )
+        external_components_path = str(FIXTURES_DIR / "external_components")
         content = content.replace("EXTERNAL_COMPONENT_PATH", external_components_path)
 
+    if shared_name is not None:
+        # _compile verifies the marked test compiles this content unmodified
+        request.node._shared_yaml_content = content
+
     return content
 
 
@@ -240,24 +270,218 @@ async def write_yaml_config(
 ) -> AsyncGenerator[ConfigWriter]:
     """Write YAML configuration to a file."""
     # Get the test name for default filename
-    test_name = request.node.name
-    base_name = test_name.replace("test_", "").split("[")[0]
+    base_name = request.node.name.replace("test_", "").partition("[")[0]
 
     async def _write_config(content: str, filename: str | None = None) -> Path:
         if filename is None:
             filename = f"{base_name}.yaml"
         config_path = integration_test_dir / filename
         loop = asyncio.get_running_loop()
-        await loop.run_in_executor(None, config_path.write_text, content)
+        await loop.run_in_executor(None, write_file, config_path, content)
         return config_path
 
     yield _write_config
 
 
+# Deliberately not CI-cached (ci.yml caches only platformio/ subpaths); stale
+# dirs for a fixture are pruned when its content hash changes.
+SHARED_BUILDS_ROOT = INTEGRATION_TESTS_ROOT / "builds"
+
+# In the dir name (not just the hash) so pruning stays inside this checkout
+_REPO_KEY = hashlib.sha256(str(REPO_ROOT).encode()).hexdigest()[:8]
+
+# Give a contended shared build lock time for a full cold compile ahead of us
+_SHARED_LOCK_TIMEOUT_S = 900
+_SHARED_LOCK_POLL_S = 0.1
+_SHARED_LOCK_REPORT_S = 30
+
+# Reclaims dirs orphaned by fixture renames or deleted checkouts
+_STALE_BUILD_MAX_AGE_S = 30 * 24 * 3600
+
+# ELF path per shared build dir; constant once compiled, so resolve it only once
+_shared_elf_paths: dict[Path, Path] = {}
+
+# Dirs this process already swept; pruning is session-scoped work
+_pruned_dirs: set[Path] = set()
+
+
+def _shared_yaml_name(request: pytest.FixtureRequest) -> str | None:
+    """Name passed to the shared_yaml marker, or None when unmarked."""
+    marker = request.node.get_closest_marker("shared_yaml")
+    if marker is None:
+        return None
+    # Exactly one \w+ positional arg: the name doubles as a build dir
+    # component, and CI test selection (script/helpers.py) parses the same shape
+    if (
+        len(marker.args) != 1
+        or marker.kwargs
+        or not re.fullmatch(r"\w+", str(marker.args[0]))
+    ):
+        raise ValueError(
+            "shared_yaml marker requires exactly one \\w+ fixture name literal"
+        )
+    return marker.args[0]
+
+
+def _shared_build_prefix(name: str) -> str:
+    return f"{name}-{_REPO_KEY}-"
+
+
+@cache
+def _shared_build_dir(name: str) -> Path:
+    """Dir keyed by checkout and fixture source, before per-test injections."""
+    key = hashlib.sha256((FIXTURES_DIR / f"{name}.yaml").read_bytes()).hexdigest()[:16]
+    return SHARED_BUILDS_ROOT / (_shared_build_prefix(name) + key)
+
+
+def _read_stamp(stamp: Path, shared_dir: Path) -> Path | None:
+    """ELF path recorded by the last completed compile, or None."""
+    try:
+        text = stamp.read_text(encoding="utf-8").strip()
+    except FileNotFoundError:
+        return None
+    except OSError as err:
+        print(f"Cannot read {stamp}: {err}")
+        return None
+    if not text:
+        print(f"Ignoring empty stamp {stamp}")
+        return None
+    built = Path(text)
+    # Never trust a stamp pointing outside its own build dir as an unlink target
+    if shared_dir.resolve() in built.resolve().parents:
+        return built
+    print(f"Ignoring stamp {stamp} pointing outside {shared_dir}")
+    return None
+
+
+def _unused_since(stale: Path, cutoff: float) -> bool:
+    """Whether a build dir looks untouched since cutoff; unknown counts as used."""
+    # Newest of the .built stamp (rewritten by every completed compile) and the
+    # dir itself (freshened by a worker claiming the dir before locking)
+    newest: float | None = None
+    for probe in (stale / ".built", stale):
+        try:
+            mtime = probe.stat().st_mtime
+        except FileNotFoundError:
+            continue
+        except NotADirectoryError:
+            return True  # a stray file where a dir should be; reclaimable
+        except OSError as err:
+            print(f"Cannot age-probe {stale}: {err}")
+            return False  # unknown never authorizes deletion
+        newest = mtime if newest is None else max(newest, mtime)
+    return newest is not None and newest < cutoff
+
+
+def _prune_stale_builds(name: str, keep: Path) -> None:
+    """Remove outdated build dirs (blocking, run in executor): this checkout's
+    other dirs for the fixture, plus anything untouched for 30 days. Tolerates
+    other workers pruning the same dirs concurrently."""
+    cutoff = time.time() - _STALE_BUILD_MAX_AGE_S
+    prefix = _shared_build_prefix(name)
+    for stale in SHARED_BUILDS_ROOT.iterdir():
+        if stale == keep:
+            continue
+        same_fixture = stale.name.startswith(prefix)
+        if not same_fixture and not _unused_since(stale, cutoff):
+            continue
+        # Creating .lock bumps the dir mtime, so remember whether the re-probe
+        # under the lock can trust it
+        lock_preexisting = (stale / ".lock").exists()
+        try:
+            lock_file = (stale / ".lock").open("w")
+        except FileNotFoundError:
+            continue  # pruned by another worker meanwhile
+        except NotADirectoryError:
+            print(f"Removing stray file {stale}")
+            stale.unlink(missing_ok=True)
+            continue
+        except OSError as err:
+            print(f"Cannot prune {stale}: {err}")
+            continue
+        with lock_file:
+            try:
+                fcntl.flock(lock_file.fileno(), fcntl.LOCK_EX | fcntl.LOCK_NB)
+            except BlockingIOError:
+                continue  # still in use by another run
+            # Re-probe under the lock: a worker freshens its dir before
+            # locking, so a just-claimed dir no longer looks unused. A dir
+            # whose .lock we just created cannot be held by anyone, and our
+            # own open bumped its mtime, so its pre-open probe stands
+            if (
+                lock_preexisting
+                and not same_fixture
+                and not _unused_since(stale, cutoff)
+            ):
+                continue
+            # rmtree tolerates races; a leftover partial tree only costs a
+            # rebuild, since the ELF is deleted before every compile
+            try:
+                rmtree(stale)
+            except OSError as err:
+                print(f"Failed to prune {stale}: {err}")
+
+
+async def _run_esphome_compile(
+    config_path: Path, cwd: Path, env: dict[str, str]
+) -> None:
+    """Run `esphome compile`, retrying up to 3 times on a segfault."""
+    max_retries = 3
+    for attempt in range(max_retries):
+        # Compile using subprocess, inheriting stdout/stderr to show progress
+        proc = await asyncio.create_subprocess_exec(
+            sys.executable,
+            "-m",
+            "esphome",
+            "compile",
+            str(config_path),
+            cwd=cwd,
+            stdout=None,  # Inherit stdout
+            stderr=None,  # Inherit stderr
+            stdin=asyncio.subprocess.DEVNULL,
+            # Start in a new process group to isolate signal handling
+            start_new_session=True,
+            env=env,
+            close_fds=False,
+        )
+        await proc.wait()
+
+        if proc.returncode == 0:
+            break
+        if proc.returncode == -11 and attempt < max_retries - 1:
+            # Segfault (-11 = SIGSEGV), retry
+            print(
+                f"Compilation segfaulted (attempt {attempt + 1}/{max_retries}), retrying..."
+            )
+            await asyncio.sleep(1)  # Brief pause before retry
+            continue
+        raise RuntimeError(
+            f"Failed to compile {config_path}, return code: {proc.returncode}. "
+            f"Run with 'pytest -s' to see compilation output."
+        )
+
+
+def _resolve_compiled_binary(config_path: Path) -> Path:
+    """Load the config to learn the compiled ELF path (blocking, run in executor)."""
+    CORE.reset()  # Reset CORE state between test runs
+    CORE.config_path = config_path
+    config = esphome.config.read_config(
+        {"command": "compile", "config": str(config_path)}
+    )
+    if config is None:
+        raise RuntimeError(f"Failed to read config from {config_path}")
+    idedata = get_idedata(config)
+    binary_path = Path(idedata.firmware_elf_path)
+    if not binary_path.exists():
+        raise RuntimeError(f"Compiled binary not found at {binary_path}")
+    return binary_path
+
+
 @pytest_asyncio.fixture
 async def compile_esphome(
     integration_test_dir: Path,
     shared_platformio_cache: Path,
+    request: pytest.FixtureRequest,
 ) -> AsyncGenerator[CompileFunction]:
     """Compile an ESPHome configuration and return the binary path."""
 
@@ -265,66 +489,96 @@ async def compile_esphome(
         # Use the shared PlatformIO cache for faster compilation
         # This avoids re-downloading dependencies for each test
         env = _get_platformio_env(shared_platformio_cache)
-
-        # Retry compilation up to 3 times if we get a segfault
-        max_retries = 3
-        for attempt in range(max_retries):
-            # Compile using subprocess, inheriting stdout/stderr to show progress
-            proc = await asyncio.create_subprocess_exec(
-                sys.executable,
-                "-m",
-                "esphome",
-                "compile",
-                str(config_path),
-                cwd=integration_test_dir,
-                stdout=None,  # Inherit stdout
-                stderr=None,  # Inherit stderr
-                stdin=asyncio.subprocess.DEVNULL,
-                # Start in a new process group to isolate signal handling
-                start_new_session=True,
-                env=env,
-                close_fds=False,
-            )
-            await proc.wait()
-
-            if proc.returncode == 0:
-                # Success!
-                break
-            if proc.returncode == -11 and attempt < max_retries - 1:
-                # Segfault (-11 = SIGSEGV), retry
-                print(
-                    f"Compilation segfaulted (attempt {attempt + 1}/{max_retries}), retrying..."
-                )
-                await asyncio.sleep(1)  # Brief pause before retry
-                continue
-            # Other error or final retry
-            raise RuntimeError(
-                f"Failed to compile {config_path}, return code: {proc.returncode}. "
-                f"Run with 'pytest -s' to see compilation output."
-            )
-
-        # Load the config to get idedata (blocking call, must use executor)
         loop = asyncio.get_running_loop()
 
-        def _read_config_and_get_binary():
-            CORE.reset()  # Reset CORE state between test runs
-            CORE.config_path = config_path
-            config = esphome.config.read_config(
-                {"command": "compile", "config": str(config_path)}
+        name = _shared_yaml_name(request)
+        if name is None:
+            await _run_esphome_compile(config_path, integration_test_dir, env)
+            return await loop.run_in_executor(
+                None, _resolve_compiled_binary, config_path
             )
-            if config is None:
-                raise RuntimeError(f"Failed to read config from {config_path}")
 
-            # Get the compiled binary path
-            idedata = get_idedata(config)
-            return Path(idedata.firmware_elf_path)
-
-        binary_path = await loop.run_in_executor(None, _read_config_and_get_binary)
-
-        if not binary_path.exists():
-            raise RuntimeError(f"Compiled binary not found at {binary_path}")
-
-        return binary_path
+        # Shared fixture: build in a hash-keyed dir so tests sharing a config
+        # pay one full compile and later only a main.cpp (port) rebuild + relink
+        shared_dir = _shared_build_dir(name)
+        shared_dir.mkdir(parents=True, exist_ok=True)
+        # Freshen the dir before locking so a concurrent age sweep, which
+        # re-probes under the lock, never reaps a dir a worker just claimed;
+        # if a peer reaped it already, the guarded lock open recreates it
+        with suppress(FileNotFoundError):
+            os.utime(shared_dir)
+        if shared_dir not in _pruned_dirs:
+            _pruned_dirs.add(shared_dir)
+            await loop.run_in_executor(None, _prune_stale_builds, name, shared_dir)
+        shared_config = shared_dir / f"{name}.yaml"
+        private_binary = integration_test_dir / f"{name}.elf"
+        content = await loop.run_in_executor(None, read_file, config_path)
+        if content != getattr(request.node, "_shared_yaml_content", None):
+            # The dir is keyed by the fixture source; a mutated config would be
+            # cached under a hash that does not describe it
+            raise RuntimeError(
+                "shared_yaml tests must compile the yaml_config content unmodified"
+            )
+        # flock serializes concurrent xdist workers; closing the fd releases it.
+        # Hand-rolled rather than filelock.FileLock: non-blocking retries keep
+        # the wait cancellable, while a blocking acquire in an executor thread
+        # would survive test cancellation holding the fd
+        try:
+            lock_file = (shared_dir / ".lock").open("w")
+        except FileNotFoundError:
+            # A peer run pruning divergent hashes reaped the dir between our
+            # mkdir and this open; recreate it and pay a full rebuild
+            shared_dir.mkdir(parents=True, exist_ok=True)
+            lock_file = (shared_dir / ".lock").open("w")
+        with lock_file:
+            start = time.monotonic()
+            last_report = start
+            while True:
+                try:
+                    fcntl.flock(lock_file.fileno(), fcntl.LOCK_EX | fcntl.LOCK_NB)
+                    break
+                except BlockingIOError:
+                    now = time.monotonic()
+                    if now - start > _SHARED_LOCK_TIMEOUT_S:
+                        raise RuntimeError(
+                            f"Timed out waiting for the {shared_dir} lock"
+                        ) from None
+                    if now - last_report >= _SHARED_LOCK_REPORT_S:
+                        last_report = now
+                        print(
+                            f"Waited {now - start:.0f}s for another worker's "
+                            f"build of {shared_dir.name}"
+                        )
+                    await asyncio.sleep(_SHARED_LOCK_POLL_S)
+            # .built carries the ELF path of the last completed compile, so
+            # later workers skip the config re-read in _resolve_compiled_binary
+            stamp = shared_dir / ".built"
+            if (built := _shared_elf_paths.get(shared_dir)) is None:
+                built = await loop.run_in_executor(None, _read_stamp, stamp, shared_dir)
+            # Delete the ELF before compiling: whatever exists afterwards is
+            # this compile's output, so no staleness check is ever needed.
+            # With no usable stamp, sweep any leftover at the known layout
+            if built is not None:
+                built.unlink(missing_ok=True)
+            else:
+                # Layout-agnostic: ESPHOME_BUILD_PATH can move the build tree
+                for leftover in shared_dir.rglob("program"):
+                    if leftover.is_file():
+                        leftover.unlink()
+            await loop.run_in_executor(
+                None, write_file_if_changed, shared_config, content
+            )
+            await _run_esphome_compile(shared_config, shared_dir, env)
+            if built is None or not built.exists():
+                built = await loop.run_in_executor(
+                    None, _resolve_compiled_binary, shared_config
+                )
+            _shared_elf_paths[shared_dir] = built
+            await loop.run_in_executor(None, write_file, stamp, str(built))
+            # Copy out before unlocking: another worker may relink firmware.elf
+            # while this test is still running its private copy
+            await loop.run_in_executor(None, shutil.copy2, built, private_binary)
+        return private_binary
 
     yield _compile
 

tests/integration/fixtures/sensor_filters_batch_window.yaml

@@ -1,58 +0,0 @@
-esphome:
-  name: test-batch-window-filters
-
-host:
-api:
-  batch_delay: 0ms  # Disable batching to receive all state updates
-logger:
-  level: DEBUG
-
-# Template sensor that we'll use to publish values
-sensor:
-  - platform: template
-    name: "Source Sensor"
-    id: source_sensor
-    accuracy_decimals: 2
-
-  # Batch window filters (window_size == send_every) - use streaming filters
-  - platform: copy
-    source_id: source_sensor
-    name: "Min Sensor"
-    id: min_sensor
-    filters:
-      - min:
-          window_size: 5
-          send_every: 5
-          send_first_at: 1
-
-  - platform: copy
-    source_id: source_sensor
-    name: "Max Sensor"
-    id: max_sensor
-    filters:
-      - max:
-          window_size: 5
-          send_every: 5
-          send_first_at: 1
-
-  - platform: copy
-    source_id: source_sensor
-    name: "Moving Avg Sensor"
-    id: moving_avg_sensor
-    filters:
-      - sliding_window_moving_average:
-          window_size: 5
-          send_every: 5
-          send_first_at: 1
-
-# Button to trigger publishing test values
-button:
-  - platform: template
-    name: "Publish Values Button"
-    id: publish_button
-    on_press:
-      - lambda: |-
-          // Publish 10 values: 1.0, 2.0, ..., 10.0
-          for (int i = 1; i <= 10; i++) {
-            id(source_sensor).publish_state(float(i));
-          }

tests/integration/fixtures/uart_mock_modbus_client_read_write.yaml

@@ -1,111 +0,0 @@
-esphome:
-  name: uart-mock-modbus-cli-rw
-
-host:
-api:
-logger:
-  level: VERBOSE
-
-external_components:
-  - source:
-      type: local
-      path: EXTERNAL_COMPONENT_PATH
-
-# Dummy uart entry to satisfy modbus's DEPENDENCIES = ["uart"]
-# The actual UART bus used is the uart_mock component below
-uart:
-  baud_rate: 115200
-  port: /dev/null
-
-# Two virtual buses looped back to each other: the client's transmissions reach the server and the
-# server's replies reach the client. auto_start so forwarding is active before the button fires.
-uart_mock:
-  - id: virtual_uart_server
-    baud_rate: 9600
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_client
-              data: !lambda return data;
-  - id: virtual_uart_client
-    baud_rate: 9600
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_server
-              data: !lambda return data;
-
-globals:
-  - id: stored_1
-    type: uint16_t
-    initial_value: "0"
-
-modbus:
-  - uart_id: virtual_uart_server
-    id: virtual_modbus_server
-    role: server
-  - uart_id: virtual_uart_client
-    id: virtual_modbus_client
-    role: client
-    turnaround_time: 10ms
-
-modbus_server:
-  - address: 1
-    modbus_id: virtual_modbus_server
-    registers:
-      # Writable + readable register: the read publishes what it returns, so the test can confirm the
-      # write half of the 0x17 ran before the read half (Modbus 6.17).
-      - address: 0x01
-        value_type: U_WORD
-        read_lambda: |-
-          id(srv_read_1).publish_state(id(stored_1));
-          return id(stored_1);
-        write_lambda: |-
-          id(stored_1) = x;
-          id(srv_write_1).publish_state(x);
-          return true;
-      # Read-only register, returned together with 0x01 by the 2-register read half.
-      - address: 0x02
-        value_type: U_WORD
-        read_lambda: return 0x00AA;
-
-sensor:
-  # Server-side observations.
-  - platform: template
-    name: "srv_write_1"
-    id: srv_write_1
-  - platform: template
-    name: "srv_read_1"
-    id: srv_read_1
-  # Client-side read-back: the values the client's on_response received.
-  - platform: template
-    name: "client_read_0"
-    id: client_read_0
-  - platform: template
-    name: "client_read_1"
-    id: client_read_1
-
-button:
-  - platform: template
-    name: "Start Scenario"
-    id: start_scenario_btn
-    on_press:
-      # FC 0x17: write reg 0x0001 = 0x1234, then read regs 0x0001..0x0002 back in the same transaction.
-      - modbus_client.read_write_multiple_registers:
-          address: 0x01
-          read_address: 0x0001
-          read_count: 2
-          write_address: 0x0001
-          values: [0x1234]
-          on_response:
-            then:
-              - lambda: |-
-                  // values is the read-back block: reg 0x0001 (must be the just-written 0x1234) and reg 0x0002.
-                  if (values.size() >= 2) {
-                    id(client_read_0).publish_state(values[0]);
-                    id(client_read_1).publish_state(values[1]);
-                  }

tests/integration/fixtures/uart_mock_modbus_custom_pdu.yaml

@@ -1,88 +0,0 @@
-esphome:
-  name: uart-mock-modbus-custom-pdu
-
-host:
-api:
-logger:
-  level: VERBOSE
-
-external_components:
-  - source:
-      type: local
-      path: EXTERNAL_COMPONENT_PATH
-
-# Dummy uart entry to satisfy modbus's DEPENDENCIES = ["uart"]
-# The actual UART bus used is the uart_mock component below
-uart:
-  baud_rate: 115200
-  port: /dev/null
-
-uart_mock:
-  - id: virtual_uart_server
-    baud_rate: 9600
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_controller
-              data: !lambda return data;
-  - id: virtual_uart_controller
-    baud_rate: 9600
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_server
-              data: !lambda return data;
-
-modbus:
-  - uart_id: virtual_uart_server
-    id: virtual_modbus_server
-    role: server
-  - uart_id: virtual_uart_controller
-    id: virtual_modbus_controller
-    role: client
-    turnaround_time: 10ms
-
-modbus_controller:
-  - address: 1
-    modbus_id: virtual_modbus_controller
-    id: modbus_controller_1
-    update_interval: 1s
-
-modbus_server:
-  - address: 1
-    modbus_id: virtual_modbus_server
-    id: modbus_server_1
-    registers:
-      - address: 0x01
-        value_type: U_WORD
-        read_lambda: return 259;
-
-sensor:
-  # Plain read to confirm the controller <-> server link is up.
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "plain_read"
-    address: 0x01
-    register_type: holding
-    value_type: U_WORD
-  # Custom PDU: read holding register 0x0001, count 1. The PDU is
-  # {function code, address hi, address lo, count hi, count lo}; the device
-  # address and CRC are added by the hub. The lambda parses the response payload
-  # (the register value, big-endian).
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "custom_read"
-    custom_pdu: [0x03, 0x00, 0x01, 0x00, 0x01]
-    lambda: |-
-      if (data.size() < 2) return {};
-      return (float) ((data[0] << 8) | data[1]);
-
-button:
-  - platform: template
-    name: "Start Scenario"
-    id: start_scenario_btn
-    # This test does not have anything to start (mock is autostart)

tests/integration/fixtures/uart_mock_modbus_deprecated_write_buffer.yaml

@@ -1,106 +0,0 @@
-esphome:
-  name: uart-mock-modbus-dep-buffer
-
-host:
-api:
-logger:
-  level: VERBOSE
-
-external_components:
-  - source:
-      type: local
-      path: EXTERNAL_COMPONENT_PATH
-
-# Dummy uart entry to satisfy modbus's DEPENDENCIES = ["uart"]
-# The actual UART bus used is the uart_mock component below
-uart:
-  baud_rate: 115200
-  port: /dev/null
-
-uart_mock:
-  - id: virtual_uart_server
-    baud_rate: 9600
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_controller
-              data: !lambda return data;
-  - id: virtual_uart_controller
-    baud_rate: 9600
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_server
-              data: !lambda return data;
-
-globals:
-  - id: reg10
-    type: uint16_t
-    initial_value: "0"
-
-modbus:
-  - uart_id: virtual_uart_server
-    id: virtual_modbus_server
-    role: server
-  - uart_id: virtual_uart_controller
-    id: virtual_modbus_controller
-    role: client
-    turnaround_time: 10ms
-
-modbus_controller:
-  - address: 1
-    modbus_id: virtual_modbus_controller
-    id: modbus_controller_1
-    update_interval: 1s
-
-modbus_server:
-  - address: 1
-    modbus_id: virtual_modbus_server
-    id: modbus_server_1
-    registers:
-      - address: 0x10
-        value_type: U_WORD
-        read_lambda: return id(reg10);
-        write_lambda: |-
-          id(reg10) = x;
-          return true;
-
-# A number whose write_lambda uses the DEPRECATED buffer parameter (fills `payload` with a legacy raw
-# frame as words: device address + function code + data) instead of the new item->write_* API. The write
-# must still land with its legacy semantics, and the one-time deprecation warning must fire only once per
-# entity no matter how many writes happen.
-number:
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "buf_number"
-    id: buf_number
-    address: 0x10
-    register_type: holding
-    value_type: U_WORD
-    min_value: 0
-    max_value: 1000
-    step: 1
-    write_lambda: |-
-      // Legacy raw frame as words: [addr 0x01 | fc 0x06], register 0x0010, value.
-      payload.push_back(0x0106);
-      payload.push_back(0x0010);
-      payload.push_back((uint16_t) x);
-      return {};
-
-# Reports the server-side register so the test can observe that the deprecated buffer write landed.
-sensor:
-  - platform: template
-    name: "written_value"
-    id: written_value
-    update_interval: 0.5s
-    lambda: "return id(reg10);"
-
-button:
-  - platform: template
-    name: "Start Scenario"
-    id: start_scenario_btn
-    # The test drives the writes via number_command; the mock is autostart.

tests/integration/fixtures/uart_mock_modbus_lambda_invert.yaml

@@ -1,95 +0,0 @@
-esphome:
-  name: uart-mock-modbus-lambda-invert
-
-host:
-api:
-logger:
-  level: VERBOSE
-
-external_components:
-  - source:
-      type: local
-      path: EXTERNAL_COMPONENT_PATH
-
-# Dummy uart entry to satisfy modbus's DEPENDENCIES = ["uart"]
-# The actual UART bus used is the uart_mock component below
-uart:
-  baud_rate: 115200
-  port: /dev/null
-
-uart_mock:
-  - id: virtual_uart_server
-    baud_rate: 9600
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_controller
-              data: !lambda return data;
-  - id: virtual_uart_controller
-    baud_rate: 9600
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_server
-              data: !lambda return data;
-
-globals:
-  - id: reg40
-    type: uint16_t
-    initial_value: "5"
-
-modbus:
-  - uart_id: virtual_uart_server
-    id: virtual_modbus_server
-    role: server
-  - uart_id: virtual_uart_controller
-    id: virtual_modbus_controller
-    role: client
-    turnaround_time: 10ms
-
-modbus_controller:
-  - address: 1
-    modbus_id: virtual_modbus_controller
-    id: modbus_controller_1
-    update_interval: 1s
-
-modbus_server:
-  - address: 1
-    modbus_id: virtual_modbus_server
-    id: modbus_server_1
-    registers:
-      - address: 0x40
-        value_type: U_WORD
-        read_lambda: return id(reg40);
-        write_lambda: id(reg40) = x; return true;
-
-# An active-low holding switch: the write_lambda inverts the wire value, but the entity must still
-# report the REQUESTED state. assumed_state keeps the register unpolled, so the published state comes
-# only from write_state() - turning ON writes 0x0000 yet the switch shows ON.
-switch:
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "invert_switch"
-    register_type: holding
-    address: 0x40
-    assumed_state: true
-    write_lambda: |-
-      return !x;
-
-sensor:
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "reg_40"
-    address: 0x40
-    register_type: holding
-    value_type: U_WORD
-
-button:
-  - platform: template
-    name: "Start Scenario"
-    id: start_scenario_btn
-    # This test does not have anything to start (mock is autostart)

tests/integration/fixtures/uart_mock_modbus_lambda_write.yaml

@@ -1,97 +0,0 @@
-esphome:
-  name: uart-mock-modbus-lambda-write
-
-host:
-api:
-logger:
-  level: VERBOSE
-
-external_components:
-  - source:
-      type: local
-      path: EXTERNAL_COMPONENT_PATH
-
-# Dummy uart entry to satisfy modbus's DEPENDENCIES = ["uart"]
-# The actual UART bus used is the uart_mock component below
-uart:
-  baud_rate: 115200
-  port: /dev/null
-
-uart_mock:
-  - id: virtual_uart_server
-    baud_rate: 9600
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_controller
-              data: !lambda return data;
-  - id: virtual_uart_controller
-    baud_rate: 9600
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_server
-              data: !lambda return data;
-
-globals:
-  - id: reg30
-    type: uint16_t
-    initial_value: "0"
-
-modbus:
-  - uart_id: virtual_uart_server
-    id: virtual_modbus_server
-    role: server
-  - uart_id: virtual_uart_controller
-    id: virtual_modbus_controller
-    role: client
-    turnaround_time: 10ms
-
-modbus_controller:
-  - address: 1
-    modbus_id: virtual_modbus_controller
-    id: modbus_controller_1
-    update_interval: 1s
-
-modbus_server:
-  - address: 1
-    modbus_id: virtual_modbus_server
-    id: modbus_server_1
-    registers:
-      - address: 0x30
-        value_type: U_WORD
-        read_lambda: return id(reg30);
-        write_lambda: id(reg30) = x; return true;
-
-# A COIL-type switch (assumed_state, write-only) whose write_lambda ignores its own coil type and instead
-# drives a HOLDING-REGISTER write on the mock server through the entity itself: `item` IS the command, so
-# item->write_single_register() sends a register write from a coil entity (cross-type). Returning nothing
-# (an empty optional) tells the write path the lambda already dispatched the frame - no default coil write.
-switch:
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "cross_switch"
-    register_type: coil
-    address: 0x00
-    assumed_state: true
-    write_lambda: |-
-      item->write_single_register(0x30, x ? 1234 : 0);
-      return {};
-
-sensor:
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "reg_30"
-    address: 0x30
-    register_type: holding
-    value_type: U_WORD
-
-button:
-  - platform: template
-    name: "Start Scenario"
-    id: start_scenario_btn
-    # This test does not have anything to start (mock is autostart)

tests/integration/fixtures/uart_mock_modbus_loopback.yaml

@@ -0,0 +1,233 @@
+esphome:
+  name: uart-mock-modbus-loopback
+
+host:
+api:
+logger:
+  level: VERBOSE
+
+external_components:
+  - source:
+      type: local
+      path: EXTERNAL_COMPONENT_PATH
+
+# Dummy uart entry to satisfy modbus's DEPENDENCIES = ["uart"]
+# The actual UART bus used is the uart_mock component below
+uart:
+  baud_rate: 115200
+  port: /dev/null
+
+# Shared loopback fixture (see the shared_yaml markers in the test file);
+# register spaces are disjoint so each test only observes its own entities.
+uart_mock:
+  - id: virtual_uart_server
+    baud_rate: 9600
+    auto_start: true
+    debug:
+    on_tx:
+      - then:
+          - uart_mock.inject_rx:
+              id: virtual_uart_controller
+              data: !lambda return data;
+  - id: virtual_uart_controller
+    baud_rate: 9600
+    auto_start: true
+    debug:
+    on_tx:
+      - then:
+          - uart_mock.inject_rx:
+              id: virtual_uart_server
+              data: !lambda return data;
+
+globals:
+  - id: reg10
+    type: uint16_t
+    initial_value: "100"
+  - id: reg11
+    type: uint16_t
+    initial_value: "200"
+  - id: reg12
+    type: uint16_t
+    initial_value: "300"
+  - id: reg13
+    type: uint16_t
+    initial_value: "0xABCD"
+  - id: reg30
+    type: uint16_t
+    initial_value: "0"
+  - id: reg40
+    type: uint16_t
+    initial_value: "5"
+  - id: reg50
+    type: uint16_t
+    initial_value: "0"
+
+modbus:
+  - uart_id: virtual_uart_server
+    id: virtual_modbus_server
+    role: server
+  - uart_id: virtual_uart_controller
+    id: virtual_modbus_controller
+    role: client
+    turnaround_time: 10ms
+
+modbus_controller:
+  - address: 1
+    modbus_id: virtual_modbus_controller
+    id: modbus_controller_1
+    update_interval: 1s
+
+modbus_server:
+  - address: 1
+    modbus_id: virtual_modbus_server
+    registers:
+      - address: 0x01
+        value_type: U_WORD
+        read_lambda: return 259;
+      - address: 0x10
+        value_type: U_WORD
+        read_lambda: return id(reg10);
+        write_lambda: id(reg10) = x; return true;
+      - address: 0x11
+        value_type: U_WORD
+        read_lambda: return id(reg11);
+        write_lambda: id(reg11) = x; return true;
+      - address: 0x12
+        value_type: U_WORD
+        read_lambda: return id(reg12);
+        write_lambda: id(reg12) = x; return true;
+      - address: 0x13
+        value_type: U_WORD
+        read_lambda: return id(reg13);
+      - address: 0x30
+        value_type: U_WORD
+        read_lambda: return id(reg30);
+        write_lambda: id(reg30) = x; return true;
+      - address: 0x40
+        value_type: U_WORD
+        read_lambda: return id(reg40);
+        write_lambda: id(reg40) = x; return true;
+      - address: 0x50
+        value_type: U_WORD
+        read_lambda: return id(reg50);
+        write_lambda: id(reg50) = x; return true;
+
+# Byte-based offset: 2 bytes -> register 0x11 (the old code folded it in as a
+# register count, hitting 0x12). assumed_state keeps the switch write-only.
+switch:
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "offset_switch"
+    register_type: holding
+    address: 0x10
+    offset: 2
+    assumed_state: true
+  # Reading switch, byte offset 6 -> register 0x13; the pre-fix resolution (0x16)
+  # would draw ILLEGAL_DATA_ADDRESS and never publish.
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "read_offset_switch"
+    register_type: holding
+    address: 0x10
+    offset: 6
+    bitmask: 0x1
+  # Coil switch whose write_lambda dispatches a holding-register write via `item`;
+  # returning an empty optional suppresses the default coil write.
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "cross_switch"
+    register_type: coil
+    address: 0x00
+    assumed_state: true
+    write_lambda: |-
+      item->write_single_register(0x30, x ? 1234 : 0);
+      return {};
+  # Active-low: the write_lambda inverts the wire value but the entity must still
+  # report the requested state (assumed_state keeps the register unpolled).
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "invert_switch"
+    register_type: holding
+    address: 0x40
+    assumed_state: true
+    write_lambda: |-
+      return !x;
+
+# Uses the deprecated buffer parameter (legacy raw frame as words); the write
+# must land and the deprecation warning must fire only once per entity.
+number:
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "buf_number"
+    id: buf_number
+    address: 0x50
+    register_type: holding
+    value_type: U_WORD
+    min_value: 0
+    max_value: 1000
+    step: 1
+    write_lambda: |-
+      // Legacy raw frame as words: [addr 0x01 | fc 0x06], register 0x0050, value.
+      payload.push_back(0x0106);
+      payload.push_back(0x0050);
+      payload.push_back((uint16_t) x);
+      return {};
+
+sensor:
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "plain_read"
+    address: 0x01
+    register_type: holding
+    value_type: U_WORD
+  # Custom PDU: read holding register 0x0001; device address and CRC are added
+  # by the hub. The lambda parses the big-endian register value.
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "custom_read"
+    custom_pdu: [0x03, 0x00, 0x01, 0x00, 0x01]
+    lambda: |-
+      if (data.size() < 2) return {};
+      return (float) ((data[0] << 8) | data[1]);
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "reg_10"
+    address: 0x10
+    register_type: holding
+    value_type: U_WORD
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "reg_11"
+    address: 0x11
+    register_type: holding
+    value_type: U_WORD
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "reg_12"
+    address: 0x12
+    register_type: holding
+    value_type: U_WORD
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "reg_30"
+    address: 0x30
+    register_type: holding
+    value_type: U_WORD
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_1
+    name: "reg_40"
+    address: 0x40
+    register_type: holding
+    value_type: U_WORD
+  # Reports the server-side register so the test can observe that the deprecated buffer write landed.
+  - platform: template
+    name: "written_value"
+    id: written_value
+    update_interval: 0.5s
+    lambda: "return id(reg50);"
+
+button:
+  - platform: template
+    name: "Start Scenario"
+    id: start_scenario_btn
+    # Nothing to start (mock is autostart); tests drive entities directly

tests/integration/fixtures/uart_mock_modbus_mesh.yaml

@@ -1,5 +1,5 @@
 esphome:
-  name: uart-mock-modbus-server-contro
+  name: uart-mock-modbus-mesh
 
 host:
 api:
@@ -17,13 +17,14 @@ uart:
   baud_rate: 115200
   port: /dev/null
 
+# Shared 3-bus mesh (see the shared_yaml markers): addr 1 = typed read-only
+# registers, addr 5 = the read/write 0x17 target, addr 2/3 on the second
+# server hub. auto_start everywhere: the controller polls at boot, so the
+# forwarding must already be live or early requests generate warnings.
+# Every test presses Start Scenario, so all merged actions fire in every test.
 uart_mock:
   - id: virtual_uart_server
     baud_rate: 9600
-    # auto_start must be true for loopback fixtures: the modbus controller
-    # polls on its update_interval immediately at boot, so the uart_mock
-    # forwarding must already be active or early requests are lost and
-    # generate modbus warnings.
     auto_start: true
     debug:
     on_tx:
@@ -31,35 +32,68 @@ uart_mock:
           - uart_mock.inject_rx:
               id: virtual_uart_controller
               data: !lambda return data;
-  - id: virtual_uart_controller
+          - uart_mock.inject_rx:
+              id: virtual_uart_server_2
+              data: !lambda return data;
+  - id: virtual_uart_server_2
     baud_rate: 9600
-    auto_start: true # See comment on virtual_uart_server above
+    auto_start: true
     debug:
     on_tx:
       - then:
           - uart_mock.inject_rx:
               id: virtual_uart_server
               data: !lambda return data;
+          - uart_mock.inject_rx:
+              id: virtual_uart_controller
+              data: !lambda return data;
+  - id: virtual_uart_controller
+    baud_rate: 9600
+    auto_start: true
+    debug:
+    on_tx:
+      - then:
+          - uart_mock.inject_rx:
+              id: virtual_uart_server
+              data: !lambda return data;
+          - uart_mock.inject_rx:
+              id: virtual_uart_server_2
+              data: !lambda return data;
+
+globals:
+  - id: stored_1
+    type: uint16_t
+    initial_value: "0"
 
 modbus:
   - uart_id: virtual_uart_server
     id: virtual_modbus_server
     role: server
+  - uart_id: virtual_uart_server_2
+    id: virtual_modbus_server_2
+    role: server
   - uart_id: virtual_uart_controller
-    id: virtual_modbus_controller
+    id: virtual_modbus_client
     role: client
     turnaround_time: 10ms
 
 modbus_controller:
   - address: 1
-    modbus_id: virtual_modbus_controller
+    modbus_id: virtual_modbus_client
     id: modbus_controller_1
     update_interval: 1s
+  - address: 2
+    modbus_id: virtual_modbus_client
+    id: modbus_controller_2
+    update_interval: 1s
+  - address: 3
+    modbus_id: virtual_modbus_client
+    id: modbus_controller_3
+    update_interval: 1s
 
 modbus_server:
   - address: 1
     modbus_id: virtual_modbus_server
-    id: modbus_server_1
     registers:
       - address: 0x01
         value_type: U_WORD
@@ -103,6 +137,34 @@ modbus_server:
       - address: 0x28
         value_type: FP32_R
         read_lambda: return 3.14;
+  - address: 5
+    modbus_id: virtual_modbus_server
+    registers:
+      # Writable + readable register: srv_write_1 plus the client's read-back
+      # confirm the write half of the 0x17 ran before the read half (Modbus 6.17).
+      - address: 0x01
+        value_type: U_WORD
+        read_lambda: return id(stored_1);
+        write_lambda: |-
+          id(stored_1) = x;
+          id(srv_write_1).publish_state(x);
+          return true;
+      # Read-only register, returned together with 0x01 by the 2-register read half.
+      - address: 0x02
+        value_type: U_WORD
+        read_lambda: return 0x00AA;
+  - address: 2
+    modbus_id: virtual_modbus_server_2
+    registers:
+      - address: 0x01
+        value_type: U_WORD
+        read_lambda: return 919;
+  - address: 3
+    modbus_id: virtual_modbus_server_2
+    registers:
+      - address: 0x01
+        value_type: U_WORD
+        read_lambda: return 929;
 
 sensor:
   - platform: modbus_controller
@@ -195,9 +257,46 @@ sensor:
     address: 0x28
     register_type: holding
     value_type: FP32_R
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_2
+    name: "multi_reg_a"
+    address: 0x01
+    register_type: holding
+    value_type: U_WORD
+  - platform: modbus_controller
+    modbus_controller_id: modbus_controller_3
+    name: "multi_reg_b"
+    address: 0x01
+    register_type: holding
+    value_type: U_WORD
+  # client_read_write observations, server- and client-side.
+  - platform: template
+    name: "srv_write_1"
+    id: srv_write_1
+  - platform: template
+    name: "client_read_0"
+    id: client_read_0
+  - platform: template
+    name: "client_read_1"
+    id: client_read_1
 
 button:
   - platform: template
     name: "Start Scenario"
     id: start_scenario_btn
-    # This test does not have anything to start (mock is autostart)
+    on_press:
+      # FC 0x17: write reg 0x0001 = 0x1234, then read regs 0x0001..0x0002 back in the same transaction.
+      - modbus_client.read_write_multiple_registers:
+          address: 5
+          read_address: 0x0001
+          read_count: 2
+          write_address: 0x0001
+          values: [0x1234]
+          on_response:
+            then:
+              - lambda: |-
+                  // values is the read-back block: reg 0x0001 (must be the just-written 0x1234) and reg 0x0002.
+                  if (values.size() >= 2) {
+                    id(client_read_0).publish_state(values[0]);
+                    id(client_read_1).publish_state(values[1]);
+                  }

tests/integration/fixtures/uart_mock_modbus_register_offset.yaml

@@ -1,138 +0,0 @@
-esphome:
-  name: uart-mock-modbus-reg-offset
-
-host:
-api:
-logger:
-  level: VERBOSE
-
-external_components:
-  - source:
-      type: local
-      path: EXTERNAL_COMPONENT_PATH
-
-# Dummy uart entry to satisfy modbus's DEPENDENCIES = ["uart"]
-# The actual UART bus used is the uart_mock component below
-uart:
-  baud_rate: 115200
-  port: /dev/null
-
-uart_mock:
-  - id: virtual_uart_server
-    baud_rate: 9600
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_controller
-              data: !lambda return data;
-  - id: virtual_uart_controller
-    baud_rate: 9600
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_server
-              data: !lambda return data;
-
-globals:
-  - id: reg10
-    type: uint16_t
-    initial_value: "100"
-  - id: reg11
-    type: uint16_t
-    initial_value: "200"
-  - id: reg12
-    type: uint16_t
-    initial_value: "300"
-  - id: reg13
-    type: uint16_t
-    initial_value: "0xABCD"
-
-modbus:
-  - uart_id: virtual_uart_server
-    id: virtual_modbus_server
-    role: server
-  - uart_id: virtual_uart_controller
-    id: virtual_modbus_controller
-    role: client
-    turnaround_time: 10ms
-
-modbus_controller:
-  - address: 1
-    modbus_id: virtual_modbus_controller
-    id: modbus_controller_1
-    update_interval: 1s
-
-modbus_server:
-  - address: 1
-    modbus_id: virtual_modbus_server
-    id: modbus_server_1
-    registers:
-      - address: 0x10
-        value_type: U_WORD
-        read_lambda: return id(reg10);
-        write_lambda: id(reg10) = x; return true;
-      - address: 0x11
-        value_type: U_WORD
-        read_lambda: return id(reg11);
-        write_lambda: id(reg11) = x; return true;
-      - address: 0x12
-        value_type: U_WORD
-        read_lambda: return id(reg12);
-        write_lambda: id(reg12) = x; return true;
-      - address: 0x13
-        value_type: U_WORD
-        read_lambda: return id(reg13);
-        write_lambda: id(reg13) = x; return true;
-
-# A holding-register switch at 0x10 with a 2-BYTE offset. offset is byte-based, so the write must target
-# register 0x10 + 2/2 = 0x11. The old (pre-fix) behavior folded offset into the address as a register
-# count, hitting 0x12 instead. assumed_state keeps the switch write-only so it does not read any register.
-switch:
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "offset_switch"
-    register_type: holding
-    address: 0x10
-    offset: 2
-    assumed_state: true
-  # A holding-register switch that READS its state. Byte offset 6 -> register 0x10 + 6/2 = 0x13. Post-fix
-  # the switch itself resolves to 0x13 (the even byte offset folds into the address as whole registers) and
-  # joins the 0x10..0x13 range, so no separate 0x13 sensor is needed. Pre-fix the whole byte offset folds
-  # into the address (0x16), where the server answers ILLEGAL_DATA_ADDRESS and the switch never publishes.
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "read_offset_switch"
-    register_type: holding
-    address: 0x10
-    offset: 6
-    bitmask: 0x1
-
-sensor:
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "reg_10"
-    address: 0x10
-    register_type: holding
-    value_type: U_WORD
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "reg_11"
-    address: 0x11
-    register_type: holding
-    value_type: U_WORD
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "reg_12"
-    address: 0x12
-    register_type: holding
-    value_type: U_WORD
-
-button:
-  - platform: template
-    name: "Start Scenario"
-    id: start_scenario_btn
-    # This test does not have anything to start (mock is autostart)

tests/integration/fixtures/uart_mock_modbus_server.yaml

@@ -1,124 +0,0 @@
-esphome:
-  name: uart-mock-modbus-server-test
-
-host:
-api:
-logger:
-  level: VERBOSE
-
-external_components:
-  - source:
-      type: local
-      path: EXTERNAL_COMPONENT_PATH
-
-# Dummy uart entry to satisfy modbus's DEPENDENCIES = ["uart"]
-# The actual UART bus used is the uart_mock component below
-uart:
-  baud_rate: 115200
-  port: /dev/null
-
-uart_mock:
-  - id: virtual_uart_dev
-    baud_rate: 9600
-    rx_full_threshold: 120
-    rx_timeout: 2
-    auto_start: false
-    debug:
-    injections:
-      - delay: 100ms
-        inject_rx: [0x01, 0x03, 0x00, 0x03, 0x00, 0x01, 0x74, 0x0A] #  Read holding register 3 on device 1 (basic_read)
-      - delay: 100ms
-        #  Read holding register 7 on device 2
-        #  Reply from device 2
-        #  Read holding register 5 on device 1 (read_after_peer_response)
-        inject_rx:
-          [
-            0x02,
-            0x03,
-            0x00,
-            0x07,
-            0x00,
-            0x01,
-            0x35,
-            0xF8,
-            0x02,
-            0x03,
-            0x02,
-            0x00,
-            0xF0,
-            0xFC,
-            0x00,
-            0x01,
-            0x03,
-            0x00,
-            0x05,
-            0x00,
-            0x01,
-            0x94,
-            0x0B,
-          ]
-      - delay: 100ms
-        inject_rx: [0x02, 0x03, 0x00, 0x07, 0x00, 0x01, 0x35, 0xF8] #  Read holding register 7 on device 2, with no response
-      - delay: 100ms
-        #  Read holding register 7 on device 2, with no response
-        #  Read holding register A on device 1 (read_after_peer_timeout)
-        inject_rx:
-          [
-            0x02,
-            0x03,
-            0x00,
-            0x07,
-            0x00,
-            0x01,
-            0x35,
-            0xF8,
-            0x01,
-            0x03,
-            0x00,
-            0x0A,
-            0x00,
-            0x01,
-            0xA4,
-            0x08,
-          ]
-
-modbus:
-  uart_id: virtual_uart_dev
-  role: server
-
-modbus_server:
-  - address: 1
-    registers:
-      - address: 0x03
-        value_type: U_WORD
-        read_lambda: |-
-          id(basic_read).publish_state(1);
-          return 1;
-      - address: 0x05
-        value_type: U_WORD
-        read_lambda: |-
-          id(read_after_peer_response).publish_state(1);
-          return 1;
-      - address: 0x0A
-        value_type: U_WORD
-        read_lambda: |-
-          id(read_after_peer_timeout).publish_state(1);
-          return 1;
-
-sensor:
-  - platform: template
-    name: "basic_read"
-    id: basic_read
-  - platform: template
-    name: "read_after_peer_response"
-    id: read_after_peer_response
-  - platform: template
-    name: "read_after_peer_timeout"
-    id: read_after_peer_timeout
-
-button:
-  - platform: template
-    name: "Start Scenario"
-    id: start_scenario_btn
-    on_press:
-      - lambda: "id(virtual_uart_dev).start_scenario();"

tests/integration/fixtures/uart_mock_modbus_server_controller_multiple.yaml

@@ -1,116 +0,0 @@
-esphome:
-  name: uart-mock-modbus-server-mult
-
-host:
-api:
-logger:
-  level: VERBOSE
-
-external_components:
-  - source:
-      type: local
-      path: EXTERNAL_COMPONENT_PATH
-
-# Dummy uart entry to satisfy modbus's DEPENDENCIES = ["uart"]
-# The actual UART bus used is the uart_mock component below
-uart:
-  baud_rate: 115200
-  port: /dev/null
-
-uart_mock:
-  - id: virtual_uart_server
-    baud_rate: 9600
-    # auto_start must be true for loopback fixtures: the modbus controller
-    # polls on its update_interval immediately at boot, so the uart_mock
-    # forwarding must already be active or early requests are lost and
-    # generate modbus warnings.
-    auto_start: true
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_controller
-              data: !lambda return data;
-          - uart_mock.inject_rx:
-              id: virtual_uart_server_2
-              data: !lambda return data;
-  - id: virtual_uart_server_2
-    baud_rate: 9600
-    auto_start: true # See comment on virtual_uart_server above
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_server
-              data: !lambda return data;
-          - uart_mock.inject_rx:
-              id: virtual_uart_controller
-              data: !lambda return data;
-  - id: virtual_uart_controller
-    baud_rate: 9600
-    auto_start: true # See comment on virtual_uart_server above
-    debug:
-    on_tx:
-      - then:
-          - uart_mock.inject_rx:
-              id: virtual_uart_server
-              data: !lambda return data;
-          - uart_mock.inject_rx:
-              id: virtual_uart_server_2
-              data: !lambda return data;
-
-modbus:
-  - uart_id: virtual_uart_server
-    id: virtual_modbus_server
-    role: server
-  - uart_id: virtual_uart_server_2
-    id: virtual_modbus_server_2
-    role: server
-  - uart_id: virtual_uart_controller
-    id: virtual_modbus_client
-    role: client
-    turnaround_time: 10ms
-
-modbus_controller:
-  - address: 1
-    modbus_id: virtual_modbus_client
-    update_interval: 1s
-    id: modbus_controller_1
-  - address: 2
-    modbus_id: virtual_modbus_client
-    update_interval: 1s
-    id: modbus_controller_2
-
-modbus_server:
-  - address: 1
-    modbus_id: virtual_modbus_server
-    registers:
-      - address: 0x01
-        value_type: U_WORD
-        read_lambda: return 919;
-  - address: 2
-    modbus_id: virtual_modbus_server_2
-    registers:
-      - address: 0x01
-        value_type: U_WORD
-        read_lambda: return 929;
-
-sensor:
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_1
-    name: "reg_u_word"
-    address: 0x01
-    register_type: holding
-    value_type: U_WORD
-  - platform: modbus_controller
-    modbus_controller_id: modbus_controller_2
-    name: "reg_u_word_2"
-    address: 0x01
-    register_type: holding
-    value_type: U_WORD
-
-button:
-  - platform: template
-    name: "Start Scenario"
-    id: start_scenario_btn
-    # This test does not have anything to start (mock is autostart)

tests/integration/fixtures/uart_mock_modbus_server_injected.yaml

@@ -1,5 +1,5 @@
 esphome:
-  name: uart-mock-modbus-srv-rw
+  name: uart-mock-modbus-srv-injected
 
 host:
 api:
@@ -17,6 +17,8 @@ uart:
   baud_rate: 115200
   port: /dev/null
 
+# Shared server-role fixture (see the shared_yaml markers in the test file);
+# the injections concatenate and each test waits only on its own sensors.
 uart_mock:
   - id: virtual_uart_dev
     baud_rate: 9600
@@ -25,18 +27,31 @@ uart_mock:
     auto_start: false
     debug:
     injections:
-      # FC 0x17 Read/Write Multiple Registers on device 1:
-      #   write reg 0x0001 = 0x1234 (qty 1), then read regs 0x0001..0x0002 (qty 2).
-      # Per Modbus 6.17 the write is performed before the read, so reg 0x0001 must
-      # read back the just-written 0x1234 in the same request.
+      - delay: 100ms
+        inject_rx: [0x01, 0x03, 0x00, 0x03, 0x00, 0x01, 0x74, 0x0A] #  Read holding register 3 on device 1 (basic_read)
+      - delay: 100ms
+        #  Read holding register 7 on device 2, its reply, then read holding
+        #  register 5 on device 1 (read_after_peer_response)
+        inject_rx: [0x02, 0x03, 0x00, 0x07, 0x00, 0x01, 0x35, 0xF8,
+                    0x02, 0x03, 0x02, 0x00, 0xF0, 0xFC,
+                    0x00, 0x01, 0x03, 0x00, 0x05, 0x00, 0x01, 0x94, 0x0B]
+      - delay: 100ms
+        inject_rx: [0x02, 0x03, 0x00, 0x07, 0x00, 0x01, 0x35, 0xF8] #  Read holding register 7 on device 2, with no response
+      - delay: 100ms
+        #  Read holding register 7 on device 2 with no response, then read
+        #  holding register A on device 1 (read_after_peer_timeout)
+        inject_rx: [0x02, 0x03, 0x00, 0x07, 0x00, 0x01, 0x35, 0xF8,
+                    0x01, 0x03, 0x00, 0x0A, 0x00, 0x01, 0xA4, 0x08]
+      # FC 0x17 on device 1: write reg 0x0001 = 0x1234 then read 0x0001..0x0002;
+      # per Modbus 6.17 the write runs first, so 0x0001 must read back 0x1234.
       - delay: 100ms
         inject_rx:
           [0x01, 0x17, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x01, 0x02, 0x12, 0x34, 0x49, 0xD8]
-      # FC 0x17: write reg 0x0003 = 0x5678 (qty 1), then read reg 0x0003 (qty 1) -
+      # FC 0x17: write reg 0x0006 = 0x5678 (qty 1), then read reg 0x0006 (qty 1) -
       # a write and read targeting a different register block.
       - delay: 100ms
         inject_rx:
-          [0x01, 0x17, 0x00, 0x03, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x02, 0x56, 0x78, 0x9B, 0x10]
+          [0x01, 0x17, 0x00, 0x06, 0x00, 0x01, 0x00, 0x06, 0x00, 0x01, 0x02, 0x56, 0x78, 0x8B, 0x55]
 
 globals:
   - id: stored_1
@@ -70,8 +85,18 @@ modbus_server:
         read_lambda: |-
           id(rw_read_2).publish_state(0x00AA);
           return 0x00AA;
-      # Second writable + readable register, targeted by the second request.
       - address: 0x03
+        value_type: U_WORD
+        read_lambda: |-
+          id(basic_read).publish_state(1);
+          return 1;
+      - address: 0x05
+        value_type: U_WORD
+        read_lambda: |-
+          id(read_after_peer_response).publish_state(1);
+          return 1;
+      # Second writable + readable register, targeted by the second FC 0x17 request.
+      - address: 0x06
         value_type: U_WORD
         read_lambda: |-
           id(rw_read_3).publish_state(id(stored_3));
@@ -80,8 +105,22 @@ modbus_server:
           id(stored_3) = x;
           id(rw_write_3).publish_state(x);
           return true;
+      - address: 0x0A
+        value_type: U_WORD
+        read_lambda: |-
+          id(read_after_peer_timeout).publish_state(1);
+          return 1;
 
 sensor:
+  - platform: template
+    name: "basic_read"
+    id: basic_read
+  - platform: template
+    name: "read_after_peer_response"
+    id: read_after_peer_response
+  - platform: template
+    name: "read_after_peer_timeout"
+    id: read_after_peer_timeout
   - platform: template
     name: "rw_write_1"
     id: rw_write_1

tests/integration/host_prefs.py

@@ -1,7 +1,7 @@
 """Helpers for manipulating the host platform's preferences file.
 
 ESPHome's host platform stores preferences in
-``~/.esphome/prefs/<app_name>.prefs`` using a simple binary layout that
+``$ESPHOME_PREFDIR/<app_name>.prefs`` using a simple binary layout that
 mirrors ``HostPreferences::sync()``:
 ``[uint32_t key][uint8_t len][uint8_t data[len]]`` per entry.
 
@@ -11,13 +11,21 @@ boot (e.g. forcing safe mode) or to clear stale state between runs.
 
 from __future__ import annotations
 
+import os
 from pathlib import Path
 import struct
 
 
 def host_prefs_path(device_name: str) -> Path:
-    """Return the on-disk prefs file path for a host-platform device."""
-    return Path.home() / ".esphome" / "prefs" / f"{device_name}.prefs"
+    """Return the on-disk prefs file path for a host-platform device.
+
+    Requires ESPHOME_PREFDIR, which the autouse isolated_preferences fixture
+    sets; refusing the ~/.esphome/prefs fallback keeps tests off real user
+    data if the fixture is ever bypassed."""
+    prefdir = os.environ.get("ESPHOME_PREFDIR")
+    if not prefdir:
+        raise RuntimeError("ESPHOME_PREFDIR is not set; refusing the real prefs dir")
+    return Path(prefdir) / f"{device_name}.prefs"
 
 
 def clear_host_prefs(device_name: str) -> None:

tests/integration/test_api_zero_psk_provisioning.py

@@ -24,7 +24,6 @@ from .types import (
     RunCompiledFunction,
 )
 
-pytestmark = pytest.mark.usefixtures("isolated_preferences")
 NEW_KEY = PROVISIONING_PSK
 
 

tests/integration/test_host_preferences_suspend_resume.py

@@ -41,15 +41,6 @@ async def _poll_until_exists(path: Path) -> None:
         await asyncio.sleep(0.05)
 
 
-@pytest.fixture(autouse=True)
-def isolated_preferences(monkeypatch: pytest.MonkeyPatch, tmp_path) -> Path:
-    """Keep host preferences per-test so this test never touches the real
-    ~/.esphome/prefs and never races other tests over ESPHOME_PREFDIR."""
-    prefdir = tmp_path / "prefs"
-    monkeypatch.setenv("ESPHOME_PREFDIR", str(prefdir))
-    return prefdir / f"{DEVICE_NAME}.prefs"
-
-
 @pytest.mark.asyncio
 async def test_host_preferences_suspend_resume(
     yaml_config: str,
@@ -58,7 +49,7 @@ async def test_host_preferences_suspend_resume(
     isolated_preferences: Path,
 ) -> None:
     """Test that a running syncer flushes, a suspended one doesn't, and resume restores flushing."""
-    pref_file = isolated_preferences
+    pref_file = isolated_preferences / f"{DEVICE_NAME}.prefs"
 
     loop = asyncio.get_running_loop()
     saved_in_memory = loop.create_future()

tests/integration/test_light_initial_state.py

@@ -11,14 +11,6 @@ from .state_utils import InitialStateHelper, require_entity
 from .types import APIClientConnectedFactory, RunCompiledFunction
 
 
-@pytest.fixture(autouse=True)
-def isolated_preferences(monkeypatch: pytest.MonkeyPatch, tmp_path) -> None:
-    """Keep host preferences per-test so RESTORE_AND_ON never loads a stale value left
-    behind by a previous run (host preferences otherwise persist to ~/.esphome/prefs,
-    keyed only by device name)."""
-    monkeypatch.setenv("ESPHOME_PREFDIR", str(tmp_path / "prefs"))
-
-
 @pytest.mark.asyncio
 async def test_light_initial_state(
     yaml_config: str,

tests/integration/test_uart_mock_modbus.py

@@ -173,6 +173,7 @@ async def test_uart_mock_modbus_no_threshold(
         _assert_no_modbus_errors(error_log_lines, warning_log_lines)
 
 
+@pytest.mark.shared_yaml("uart_mock_modbus_server_injected")
 @pytest.mark.asyncio
 async def test_uart_mock_modbus_server(
     yaml_config: str,
@@ -203,6 +204,7 @@ async def test_uart_mock_modbus_server(
         _assert_no_modbus_errors(error_log_lines, warning_log_lines)
 
 
+@pytest.mark.shared_yaml("uart_mock_modbus_server_injected")
 @pytest.mark.asyncio
 async def test_uart_mock_modbus_server_read_write(
     yaml_config: str,
@@ -231,8 +233,8 @@ async def test_uart_mock_modbus_server_read_write(
             "rw_write_1": 4660,  # 0x1234 written to reg 0x0001
             "rw_read_1": 4660,  # reg 0x0001 reads back the just-written value
             "rw_read_2": 170,  # 0x00AA read from reg 0x0002 in the same request
-            "rw_write_3": 22136,  # 0x5678 written to reg 0x0003
-            "rw_read_3": 22136,  # reg 0x0003 reads back the just-written value
+            "rw_write_3": 22136,  # 0x5678 written to reg 0x0006
+            "rw_read_3": 22136,  # reg 0x0006 reads back the just-written value
         }
     )
 
@@ -241,7 +243,8 @@ async def test_uart_mock_modbus_server_read_write(
         api_client_connected() as client,
     ):
         await tracker.setup_and_start_scenario(client)
-        await tracker.await_all(futures)
+        # The FC 0x17 injections fire last, behind four earlier 100ms delays
+        await tracker.await_all(futures, timeout=4.0)
         _assert_no_modbus_errors(error_log_lines, warning_log_lines)
 
 
@@ -296,6 +299,7 @@ async def test_uart_mock_modbus_server_read_write_invalid(
     )
 
 
+@pytest.mark.shared_yaml("uart_mock_modbus_mesh")
 @pytest.mark.asyncio
 async def test_uart_mock_modbus_server_controller(
     yaml_config: str,
@@ -485,6 +489,7 @@ async def test_uart_mock_modbus_server_controller_bits(
         _assert_no_modbus_errors(error_log_lines, warning_log_lines)
 
 
+@pytest.mark.shared_yaml("uart_mock_modbus_mesh")
 @pytest.mark.asyncio
 async def test_uart_mock_modbus_server_controller_multiple(
     yaml_config: str,
@@ -495,7 +500,7 @@ async def test_uart_mock_modbus_server_controller_multiple(
 
     line_callback, error_log_lines, warning_log_lines = _make_modbus_line_callback()
 
-    expected_values = {"reg_u_word": 919, "reg_u_word_2": 929}
+    expected_values = {"multi_reg_a": 919, "multi_reg_b": 929}
     tracker = SensorTracker(list(expected_values.keys()))
     futures = tracker.expect_all(expected_values)
 
@@ -706,6 +711,7 @@ async def test_uart_mock_modbus_shared_address(
         _assert_no_modbus_errors(error_log_lines, warning_log_lines)
 
 
+@pytest.mark.shared_yaml("uart_mock_modbus_loopback")
 @pytest.mark.asyncio
 async def test_uart_mock_modbus_custom_pdu(
     yaml_config: str,
@@ -932,6 +938,7 @@ async def test_uart_mock_modbus_broadcast_write(
         _assert_no_modbus_errors(error_log_lines, warning_log_lines)
 
 
+@pytest.mark.shared_yaml("uart_mock_modbus_mesh")
 @pytest.mark.asyncio
 async def test_uart_mock_modbus_client_read_write(
     yaml_config: str,
@@ -947,9 +954,7 @@ async def test_uart_mock_modbus_client_read_write(
     """
     line_callback, error_log_lines, warning_log_lines = _make_modbus_line_callback()
 
-    tracker = SensorTracker(
-        ["srv_write_1", "srv_read_1", "client_read_0", "client_read_1"]
-    )
+    tracker = SensorTracker(["srv_write_1", "client_read_0", "client_read_1"])
     futures = tracker.expect_all(
         {
             "srv_write_1": 4660,  # server wrote 0x1234 to reg 0x0001
@@ -967,6 +972,7 @@ async def test_uart_mock_modbus_client_read_write(
         _assert_no_modbus_errors(error_log_lines, warning_log_lines)
 
 
+@pytest.mark.shared_yaml("uart_mock_modbus_loopback")
 @pytest.mark.asyncio
 async def test_uart_mock_modbus_register_offset(
     yaml_config: str,
@@ -1022,6 +1028,7 @@ async def test_uart_mock_modbus_register_offset(
         )
 
 
+@pytest.mark.shared_yaml("uart_mock_modbus_loopback")
 @pytest.mark.asyncio
 async def test_uart_mock_modbus_lambda_write(
     yaml_config: str,
@@ -1058,6 +1065,7 @@ async def test_uart_mock_modbus_lambda_write(
         await tracker.await_change(wrote_30, "reg_30", timeout=4.0)
 
 
+@pytest.mark.shared_yaml("uart_mock_modbus_loopback")
 @pytest.mark.asyncio
 async def test_uart_mock_modbus_lambda_invert(
     yaml_config: str,
@@ -1113,6 +1121,7 @@ async def test_uart_mock_modbus_lambda_invert(
         )
 
 
+@pytest.mark.shared_yaml("uart_mock_modbus_loopback")
 @pytest.mark.asyncio
 async def test_uart_mock_modbus_deprecated_write_buffer(
     yaml_config: str,

tests/script/test_helpers.py

@@ -2122,6 +2122,34 @@ def test_get_cpp_changed_components_independent_of_cwd(
     ) == ["time"]
 
 
+def test_fixture_map_includes_shared_yaml_markers() -> None:
+    """Fixtures named only by shared_yaml markers must map to their test file."""
+    helpers.get_fixture_to_test_files.cache_clear()
+    mapping = helpers.get_fixture_to_test_files()
+    for fixture in (
+        "uart_mock_modbus_loopback",
+        "uart_mock_modbus_mesh",
+        "uart_mock_modbus_server_injected",
+    ):
+        assert mapping[fixture] == frozenset(
+            {"tests/integration/test_uart_mock_modbus.py"}
+        )
+
+
+def test_no_orphan_integration_fixtures() -> None:
+    """Every fixture must reach CI test selection; an orphan selects nothing."""
+    helpers.get_fixture_to_test_files.cache_clear()
+    mapping = helpers.get_fixture_to_test_files()
+    fixtures_dir = (Path(__file__).parent.parent / "integration" / "fixtures").resolve()
+    fixtures = list(fixtures_dir.glob("*.yaml"))
+    assert fixtures, f"no fixtures found under {fixtures_dir}"
+    # cache_init is covered via INTEGRATION_TESTS_TRIGGER_FILES instead
+    orphans = [
+        f.stem for f in fixtures if f.stem != "cache_init" and f.stem not in mapping
+    ]
+    assert not orphans, f"fixtures invisible to CI test selection: {orphans}"
+
+
 def test_lpt_partition_balances_skewed_weights() -> None:
     """Heavy items spread across groups instead of clustering."""
     items = [f"i{n}" for n in range(6)]

tests/script/test_platformio_install_deps.py

@@ -35,8 +35,8 @@ def _load_script():
 def test_spec_key_collapses_destinations() -> None:
     """Two specs delivering one package share a directory and one key."""
     mod = _load_script()
-    assert mod.spec_key("esphome/noise-c @ 0.1.26") == "noise-c"
-    assert mod.spec_key("esphome/noise-c@0.1.26") == "noise-c"
+    assert mod.spec_key("esphome/noise-c @ 0.1.24") == "noise-c"
+    assert mod.spec_key("esphome/noise-c@0.1.24") == "noise-c"
     assert mod.spec_key("ESP32Async/AsyncTCP @ ^3.4.10") == mod.spec_key(
         "esp32async/asynctcp @ 3.5.0"
     )
@@ -54,23 +54,23 @@ def test_parse_specs_and_cli_args(tmp_path: Path) -> None:
         "[env:a]\n"
         "platform = fake/platform@1\n"
         "lib_deps =\n"
-        "    esphome/noise-c @ 0.1.26\n"
+        "    esphome/noise-c @ 0.1.24\n"
         "    ${common.lib_deps}\n"
         "    internal_lib\n"
         "[env:b]\n"
         "lib_deps =\n"
-        "    esphome/noise-c @ 0.1.26\n"
+        "    esphome/noise-c @ 0.1.24\n"
     )
     mod = _load_script()
     args = Namespace(libraries=True, platforms=True, tools=False)
     libs, platforms, tools = mod.parse_specs(str(ini), args)
     # exact-string duplicates collapse; distinct version pins survive
-    assert libs == ["esphome/noise-c @ 0.1.26"]
+    assert libs == ["esphome/noise-c @ 0.1.24"]
     assert platforms == ["fake/platform@1"]
     assert tools == []
     assert mod.build_cli_args(libs, platforms, tools) == [
         "-l",
-        "esphome/noise-c @ 0.1.26",
+        "esphome/noise-c @ 0.1.24",
         "-p",
         "fake/platform@1",
     ]
@@ -162,13 +162,13 @@ def test_parallel_install_behavior(tmp_path: Path) -> None:
     mod.parallel_install(
         cls,
         [
-            "esphome/noise-c @ 0.1.26",
-            "esphome/noise-c @ 0.1.26",
+            "esphome/noise-c @ 0.1.24",
+            "esphome/noise-c @ 0.1.24",
             "esphome/already @ 1.0",
             "https://x/framework.tar.xz",
         ],
     )
-    assert cls.calls == ["esphome/noise-c @ 0.1.26"]
+    assert cls.calls == ["esphome/noise-c @ 0.1.24"]
     assert cls.lock_events == ["lock", "unlock"]
 
 
@@ -205,7 +205,7 @@ def test_parallel_install_runs_dependency_waves(tmp_path: Path) -> None:
     mod = _load_script()
     cls = _reset_fake(str(tmp_path))
     cls.deps = {
-        "esphome/noise-c @ 0.1.26": [
+        "esphome/noise-c @ 0.1.24": [
             {"owner": "esphome", "name": "libsodium", "version": "^1.0"},
             {"name": "SPI"},
         ],
@@ -213,12 +213,12 @@ def test_parallel_install_runs_dependency_waves(tmp_path: Path) -> None:
             {"owner": "esphome", "name": "libsodium", "version": "^1.0"},
         ],
     }
-    mod.parallel_install(cls, ["esphome/noise-c @ 0.1.26", "esphome/wg @ 1.0"])
+    mod.parallel_install(cls, ["esphome/noise-c @ 0.1.24", "esphome/wg @ 1.0"])
     assert len(cls.calls) == 3  # the shared dep installs exactly once
     assert {mod.spec_key(c) for c in cls.calls} == {"noise-c", "wg", "libsodium"}
     # Wave-1 strings carry no compatibility; the dependency wave does
     compats = dict(cls.compat_calls)
-    assert compats["esphome/noise-c @ 0.1.26"] is None
+    assert compats["esphome/noise-c @ 0.1.24"] is None
     dep_compat = next(v for k, v in cls.compat_calls if "libsodium" in k)
     assert dep_compat is not None  # mirrors pio's install_dependency
 
@@ -229,11 +229,11 @@ def test_dependency_wave_excludes_url_specs(tmp_path: Path) -> None:
     mod = _load_script()
     cls = _reset_fake(str(tmp_path))
     cls.deps = {
-        "esphome/noise-c @ 0.1.26": [
+        "esphome/noise-c @ 0.1.24": [
             {"name": "vendored", "version": "https://github.com/x/y.git"},
         ],
     }
-    mod.parallel_install(cls, ["esphome/noise-c @ 0.1.26"])
+    mod.parallel_install(cls, ["esphome/noise-c @ 0.1.24"])
     assert {mod.spec_key(c) for c in cls.calls} == {"noise-c"}
 
 
@@ -348,13 +348,13 @@ def test_warm_store_still_walks_dependencies(tmp_path: Path) -> None:
     """Already-installed top-level packages still feed the dependency
     wave; a warm store can be missing a transitive dep."""
     mod = _load_script()
-    cls = _reset_fake(str(tmp_path), installed={"esphome/noise-c @ 0.1.26"})
+    cls = _reset_fake(str(tmp_path), installed={"esphome/noise-c @ 0.1.24"})
     cls.deps = {
-        "esphome/noise-c @ 0.1.26": [
+        "esphome/noise-c @ 0.1.24": [
             {"owner": "esphome", "name": "libsodium", "version": "^1.0"},
         ],
     }
-    mod.parallel_install(cls, ["esphome/noise-c @ 0.1.26"])
+    mod.parallel_install(cls, ["esphome/noise-c @ 0.1.24"])
     assert [mod.spec_key(c) for c in cls.calls] == ["libsodium"]
 
 

tests/script/test_sync_dependency_versions.py

@@ -0,0 +1,219 @@
+"""Unit tests for script/sync_dependency_versions.py."""
+
+from pathlib import Path
+import subprocess
+import sys
+
+import pytest
+import yamlrocks
+
+sys.path.insert(0, str((Path(__file__).parent / ".." / ".." / "script").resolve()))
+
+import sync_dependency_versions as sync_mod  # noqa: E402
+
+PRECOMMIT = """\
+# See https://pre-commit.com for more information
+repos:
+  - repo: https://github.com/astral-sh/ruff-pre-commit
+    # Ruff version.
+    rev: v0.1.0
+    hooks:
+      - id: ruff
+  - repo: https://github.com/PyCQA/flake8
+    rev: 7.0.0
+    hooks:
+      - id: flake8
+  - repo: https://github.com/asottile/pyupgrade
+    rev: v3.0.0
+    hooks:
+      - id: pyupgrade
+  - repo: https://github.com/pre-commit/mirrors-clang-format
+    rev: v13.0.1
+    hooks:
+      - id: clang-format
+  - repo: https://github.com/adrienverge/yamllint.git
+    rev: v1.0.0
+    hooks:
+      - id: yamllint
+  - repo: local
+    hooks:
+      - id: pylint
+"""
+
+REQ_TEST = """\
+pylint==4.0.8
+flake8==7.1.0
+ruff==0.2.0  # comment
+pyupgrade==3.0.0
+"""
+
+REQ_DEV = """\
+clang-format==13.0.1
+yamllint==1.0.0
+"""
+
+RUFF_REPO = "https://github.com/astral-sh/ruff-pre-commit"
+DUPLICATE_RUFF_BLOCK = f"  - repo: {RUFF_REPO}\n    rev: v0.3.0\n    hooks: []\n"
+
+EXPECTED_DRIFT = ["ruff: 0.1.0 -> 0.2.0", "flake8: 7.0.0 -> 7.1.0"]
+EXPECTED_PRECOMMIT = PRECOMMIT.replace("rev: v0.1.0", "rev: v0.2.0").replace(
+    "rev: 7.0.0", "rev: 7.1.0"
+)
+
+
+@pytest.fixture
+def root(tmp_path: Path) -> Path:
+    """A fake checkout where ruff (v-prefixed) and flake8 (bare) have drifted."""
+    (tmp_path / ".pre-commit-config.yaml").write_text(PRECOMMIT)
+    (tmp_path / "requirements_test.txt").write_text(REQ_TEST)
+    (tmp_path / "requirements_dev.txt").write_text(REQ_DEV)
+    return tmp_path
+
+
+def _load(text: str) -> object:
+    return yamlrocks.loads(text.encode(), option=yamlrocks.OPT_ROUND_TRIP)
+
+
+@pytest.mark.parametrize(
+    ("requirements", "expected"),
+    [
+        ("prek==0.5.1  # comment\n", "0.5.1"),
+        ("Prek==0.5.1\n", "0.5.1"),
+        ("other==1.0\nprek==0.5.1\n", "0.5.1"),
+        ("prek>=0.5.1\n", None),
+        ("prek-extra==0.5.1\n", None),
+        ("", None),
+    ],
+)
+def test_read_requirement_version(requirements: str, expected: str | None) -> None:
+    assert sync_mod.read_requirement_version(requirements, "prek") == expected
+
+
+def test_find_repo_entry() -> None:
+    entry = sync_mod.find_repo_entry(_load(PRECOMMIT), RUFF_REPO)
+    assert entry["rev"] == "v0.1.0"
+
+
+@pytest.mark.parametrize(
+    ("text", "message"),
+    [
+        ("hooks: []\n", "missing key 'repos'"),
+        ("repos:\n  - rev: 1.0.0\n", "missing key 'repo'"),
+        (PRECOMMIT + DUPLICATE_RUFF_BLOCK, "found 2"),
+        ("repos:\n  - repo: other\n    rev: 1.0.0\n", "found 0"),
+    ],
+)
+def test_find_repo_entry_errors(text: str, message: str) -> None:
+    with pytest.raises(sync_mod.SyncError, match=message):
+        sync_mod.find_repo_entry(_load(text), RUFF_REPO)
+
+
+@pytest.mark.parametrize(
+    ("rev", "expected"),
+    [("v0.1.0", ("v", "0.1.0")), ("7.0.0", ("", "7.0.0")), ("'1.0'", ("", "1.0"))],
+)
+def test_current_rev(rev: str, expected: tuple[str, str]) -> None:
+    doc = _load(f"repos:\n  - repo: {RUFF_REPO}\n    rev: {rev}\n")
+    assert sync_mod.current_rev(doc["repos"][0], RUFF_REPO) == expected
+
+
+@pytest.mark.parametrize(
+    ("block", "message"),
+    [("    hooks: []\n", "has no rev"), ("    rev: 1.0\n", "not a string: 1.0")],
+)
+def test_current_rev_errors(block: str, message: str) -> None:
+    doc = _load(f"repos:\n  - repo: {RUFF_REPO}\n{block}")
+    with pytest.raises(sync_mod.SyncError, match=message):
+        sync_mod.current_rev(doc["repos"][0], RUFF_REPO)
+
+
+def test_sync_reports_without_writing(root: Path) -> None:
+    assert sync_mod.sync(root, write=False) == EXPECTED_DRIFT
+    assert (root / ".pre-commit-config.yaml").read_text() == PRECOMMIT
+
+
+def test_sync_writes_keeps_layout_and_is_idempotent(root: Path) -> None:
+    assert sync_mod.sync(root, write=True) == EXPECTED_DRIFT
+    assert (root / ".pre-commit-config.yaml").read_text() == EXPECTED_PRECOMMIT
+    assert sync_mod.sync(root, write=True) == []
+
+
+def test_sync_does_not_touch_a_config_that_matches(root: Path) -> None:
+    (root / ".pre-commit-config.yaml").write_text(EXPECTED_PRECOMMIT)
+    before = (root / ".pre-commit-config.yaml").stat().st_mtime_ns
+    assert sync_mod.sync(root, write=True) == []
+    assert (root / ".pre-commit-config.yaml").stat().st_mtime_ns == before
+
+
+def test_sync_missing_requirement_pin(root: Path) -> None:
+    (root / "requirements_dev.txt").write_text("")
+    with pytest.raises(sync_mod.SyncError, match="no 'clang-format==' pin"):
+        sync_mod.sync(root, write=True)
+
+
+def test_sync_propagates_config_errors(root: Path) -> None:
+    (root / ".pre-commit-config.yaml").write_text(PRECOMMIT + DUPLICATE_RUFF_BLOCK)
+    with pytest.raises(sync_mod.SyncError, match="found 2"):
+        sync_mod.sync(root, write=True)
+
+
+def test_main_check_reports_drift(
+    root: Path, capsys: pytest.CaptureFixture[str]
+) -> None:
+    assert sync_mod.main(["--check", "--root", str(root)]) == 1
+    assert capsys.readouterr().out.splitlines() == EXPECTED_DRIFT
+    assert (root / ".pre-commit-config.yaml").read_text() == PRECOMMIT
+
+
+def test_main_writes_then_check_is_clean(
+    root: Path, capsys: pytest.CaptureFixture[str]
+) -> None:
+    assert sync_mod.main(["--root", str(root)]) == 0
+    assert capsys.readouterr().out.splitlines() == EXPECTED_DRIFT
+    assert sync_mod.main(["--check", "--root", str(root)]) == 0
+    assert capsys.readouterr().out == ""
+
+
+def test_main_reports_sync_error(
+    root: Path, capsys: pytest.CaptureFixture[str]
+) -> None:
+    (root / "requirements_dev.txt").write_text("")
+    assert sync_mod.main(["--root", str(root)]) == 1
+    assert (
+        "error: requirements_dev.txt: no 'clang-format==' pin"
+        in capsys.readouterr().err
+    )
+
+
+def test_main_defaults_to_repo_root(monkeypatch: pytest.MonkeyPatch) -> None:
+    seen: dict[str, object] = {}
+
+    def fake_sync(root: Path, *, write: bool) -> list[str]:
+        seen["root"] = root
+        seen["write"] = write
+        return []
+
+    monkeypatch.setattr(sync_mod, "sync", fake_sync)
+    assert sync_mod.main([]) == 0
+    assert seen == {"root": sync_mod.REPO_ROOT, "write": True}
+
+
+def test_repository_is_in_sync() -> None:
+    """The real checkout must match; a failure here means a rev has drifted.
+
+    Also proves every SYNC_TARGETS entry still resolves in the real files.
+    """
+    assert sync_mod.sync(sync_mod.REPO_ROOT, write=False) == []
+
+
+def test_cli_entry_point(root: Path) -> None:
+    """Run the script the way the workflow does, as a subprocess."""
+    script = Path(sync_mod.__file__)
+    result = subprocess.run(
+        [sys.executable, str(script), "--check", "--root", str(root)],
+        capture_output=True,
+        text=True,
+        check=False,
+    )
+    assert result.returncode == 1
+    assert result.stdout.splitlines() == EXPECTED_DRIFT

tests/unit_tests/test_espota2.py

@@ -416,9 +416,6 @@ def test_perform_ota_no_auth(
         "Update took 14.00 seconds (prepare 2.00, upload 5.00, commit 7.00)"
         in caplog.text
     )
-    # The data phase timeout must outlast the device's 105 s data timeout
-    mock_socket.settimeout.assert_any_call(espota2.DATA_PHASE_TIMEOUT)
-    assert espota2.DATA_PHASE_TIMEOUT > 105.0
 
 
 @pytest.mark.usefixtures("mock_time")

tests/unit_tests/test_platformio_prefetch.py

@@ -1663,7 +1663,7 @@ def test_preinstall_runs_dependency_waves(tmp_path: Path) -> None:
         {"name": "SPI"},
     ]
     m.dependency_to_spec.side_effect = lambda dep: _FakeSpec(name=dep["name"])
-    pf._preinstall(m, [("noise-c@0.1.26", _FakeSpec(name="noise-c"))])
+    pf._preinstall(m, [("noise-c@0.1.24", _FakeSpec(name="noise-c"))])
     assert installed == ["noise-c", "libsodium"]  # dep deduped, SPI left out
     # The dep wave carries its compatibility so _install searches qualified
     dep_call = m._install.call_args_list[-1]
@@ -1683,7 +1683,7 @@ def test_preinstall_dependency_wave_skips_seen_names(tmp_path: Path) -> None:
     m._install.side_effect = lambda spec, skip_dependencies, compatibility=None: (
         installed.append(getattr(spec, "name", str(spec)))
     )
-    pf._preinstall(m, [("noise-c@0.1.26", _FakeSpec(name="noise-c"))])
+    pf._preinstall(m, [("noise-c@0.1.24", _FakeSpec(name="noise-c"))])
     assert installed == ["noise-c"]